[clang] [clang][FMV] Do not omit explicit default target_version attribute. (PR #96628)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `lldb-x86_64-debian` running on `lldb-x86_64-debian` while building `clang` at step 6 "test".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/162/builds/1430

Here is the relevant piece of the build log for the reference:
```
Step 6 (test) failure: build (failure)
...
PASS: lldb-api :: macosx/load-kext/TestLoadKext.py (1080 of 2628)
UNSUPPORTED: lldb-api :: python_api/target-arch-from-module/TestTargetArchFromModule.py (1081 of 2628)
UNSUPPORTED: lldb-api :: lang/objc/global_ptrs/TestGlobalObjects.py (1082 of 2628)
PASS: lldb-api :: commands/version/TestVersion.py (1083 of 2628)
UNSUPPORTED: lldb-api :: lang/objc/modules-inline-functions/TestModulesInlineFunctions.py (1084 of 2628)
UNSUPPORTED: lldb-api :: lang/objc/foundation/TestObjCMethods.py (1085 of 2628)
UNSUPPORTED: lldb-api :: functionalities/type_lookup/TestTypeLookup.py (1086 of 2628)
UNSUPPORTED: lldb-api :: macosx/stack-corefile/TestStackCorefile.py (1087 of 2628)
UNSUPPORTED: lldb-api :: functionalities/interactive_scripted_process/TestInteractiveScriptedProcess.py (1088 of 2628)
UNSUPPORTED: lldb-api :: commands/expression/weak_symbols/TestWeakSymbols.py (1089 of 2628)
FAIL: lldb-shell :: SymbolFile/DWARF/x86/dwp-foreign-type-units.cpp (1090 of 2628)
******************** TEST 'lldb-shell :: SymbolFile/DWARF/x86/dwp-foreign-type-units.cpp' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 21: /home/worker/2.0.1/lldb-x86_64-debian/build/bin/clang --target=specify-a-target-or-use-a-_host-substitution -target x86_64-pc-linux -gdwarf-5 -gsplit-dwarf    -fdebug-types-section -gpubnames -c /home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/Shell/SymbolFile/DWARF/x86/dwp-foreign-type-units.cpp -o /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/SymbolFile/DWARF/x86/Output/dwp-foreign-type-units.cpp.tmp.main.o
+ /home/worker/2.0.1/lldb-x86_64-debian/build/bin/clang --target=specify-a-target-or-use-a-_host-substitution -target x86_64-pc-linux -gdwarf-5 -gsplit-dwarf -fdebug-types-section -gpubnames -c /home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/Shell/SymbolFile/DWARF/x86/dwp-foreign-type-units.cpp -o /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/SymbolFile/DWARF/x86/Output/dwp-foreign-type-units.cpp.tmp.main.o
RUN: at line 23: /home/worker/2.0.1/lldb-x86_64-debian/build/bin/clang --target=specify-a-target-or-use-a-_host-substitution -target x86_64-pc-linux -gdwarf-5 -gsplit-dwarf -DVARIANT    -fdebug-types-section -gpubnames -c /home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/Shell/SymbolFile/DWARF/x86/dwp-foreign-type-units.cpp -o /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/SymbolFile/DWARF/x86/Output/dwp-foreign-type-units.cpp.tmp.foo.o
+ /home/worker/2.0.1/lldb-x86_64-debian/build/bin/clang --target=specify-a-target-or-use-a-_host-substitution -target x86_64-pc-linux -gdwarf-5 -gsplit-dwarf -DVARIANT -fdebug-types-section -gpubnames -c /home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/Shell/SymbolFile/DWARF/x86/dwp-foreign-type-units.cpp -o /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/SymbolFile/DWARF/x86/Output/dwp-foreign-type-units.cpp.tmp.foo.o
RUN: at line 25: /home/worker/2.0.1/lldb-x86_64-debian/build/bin/ld.lld /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/SymbolFile/DWARF/x86/Output/dwp-foreign-type-units.cpp.tmp.main.o /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/SymbolFile/DWARF/x86/Output/dwp-foreign-type-units.cpp.tmp.foo.o -o /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/SymbolFile/DWARF/x86/Output/dwp-foreign-type-units.cpp.tmp
+ /home/worker/2.0.1/lldb-x86_64-debian/build/bin/ld.lld /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/SymbolFile/DWARF/x86/Output/dwp-foreign-type-units.cpp.tmp.main.o /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/SymbolFile/DWARF/x86/Output/dwp-foreign-type-units.cpp.tmp.foo.o -o /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/SymbolFile/DWARF/x86/Output/dwp-foreign-type-units.cpp.tmp
ld.lld: warning: cannot find entry symbol _start; not setting start address
RUN: at line 28: rm -f /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/SymbolFile/DWARF/x86/Output/dwp-foreign-type-units.cpp.tmp.dwp
+ rm -f /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/SymbolFile/DWARF/x86/Output/dwp-foreign-type-units.cpp.tmp.dwp
RUN: at line 29: /home/worker/2.0.1/lldb-x86_64-debian/build/bin/lldb --no-lldbinit -S /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/lit-lldb-init-quiet    -o "type lookup IntegerType"    -o "type lookup FloatType"    -o "type lookup CustomType"    -b /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/SymbolFile/DWARF/x86/Output/dwp-foreign-type-units.cpp.tmp | /home/worker/2.0.1/lldb-x86_64-debian/build/bin/FileCheck /home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/Shell/SymbolFile/DWARF/x86/dwp-foreign-type-units.cpp --check-prefix=NODWP
+ /home/worker/2.0.1/lldb-x86_64-debian/build/bin/lldb --no-lldbinit -S /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/lit-lldb-init-quiet -o 'type lookup IntegerType' -o 'type lookup FloatType' -o 'type lookup CustomType' -b /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/test/Shell/SymbolFile/DWARF/x86/Output/dwp-foreign-type-units.cpp.tmp
+ /home/worker/2.0.1/lldb-x86_64-debian/build/bin/FileCheck /home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/Shell/SymbolFile/DWARF/x86/dwp-foreign-type-units.cpp --check-prefix=NODWP
/home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/Shell/SymbolFile/DWARF/x86/dwp-foreign-type-units.cpp:37:11: error: NODWP: expected string not found in input
// NODWP: (lldb) type lookup FloatType
          ^
<stdin>:20:22: note: scanning from here
 typedef unsigned int IntegerType;
                     ^
<stdin>:21:3: note: possible intended match here
 typedef float FloatType;
  ^

Input file: <stdin>
Check file: /home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/Shell/SymbolFile/DWARF/x86/dwp-foreign-type-units.cpp

-dump-input=help explains the following input dump.

Input was:
<<<<<<
            .
            .
            .
           15:  typedef double FloatType; 

```

https://github.com/llvm/llvm-project/pull/96628