[clang] [Clang][SYCL] Introduce clang-sycl-linker to link SYCL offloading device code (Part 1 of many) (PR #112245)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `flang-aarch64-sharedlibs` running on `linaro-flang-aarch64-sharedlibs` while building `clang` at step 5 "build-unified-tree".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/80/builds/5662

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 5 (build-unified-tree) failure: build (failure)
...
770.201 [1161/12/6289] Generating ../../../../libexec/intercept-c++
770.201 [1161/11/6290] Generating ../../../../lib/libscanbuild/resources/selectable.js
770.202 [1161/10/6291] Generating ../../../../lib/libscanbuild/shell.py
770.207 [1161/9/6292] Generating ../../../../libexec/intercept-cc
770.220 [1161/8/6293] Generating ../../../../lib/libscanbuild/resources/scanview.css
770.278 [1161/7/6294] Generating ../../../../lib/libscanbuild/resources/sorttable.js
770.342 [1161/6/6295] Linking CXX shared library lib/libclangParse.so.20.0git
770.357 [1159/7/6296] Creating library symlink lib/libclangParse.so
770.364 [1159/6/6297] Generating ../../../../bin/scan-view
770.394 [1156/8/6298] Linking CXX executable bin/clang-sycl-linker
FAILED: bin/clang-sycl-linker 
: && /usr/local/bin/c++ -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -fno-common -Woverloaded-virtual -Wno-nested-anon-types -O3 -DNDEBUG -Wl,-rpath-link,/home/tcwg-buildbot/worker/flang-aarch64-sharedlibs/build/./lib  -Wl,--gc-sections tools/clang/tools/clang-sycl-linker/CMakeFiles/clang-sycl-linker.dir/ClangSYCLLinker.cpp.o -o bin/clang-sycl-linker  -Wl,-rpath,"\$ORIGIN/../lib:/home/tcwg-buildbot/worker/flang-aarch64-sharedlibs/build/lib:"  lib/libLLVMAArch64CodeGen.so.20.0git  lib/libLLVMAArch64AsmParser.so.20.0git  lib/libLLVMAArch64Disassembler.so.20.0git  lib/libLLVMOption.so.20.0git  lib/libclangBasic.so.20.0git  lib/libLLVMAArch64Desc.so.20.0git  lib/libLLVMAArch64Info.so.20.0git  lib/libLLVMAArch64Utils.so.20.0git  -Wl,-rpath-link,/home/tcwg-buildbot/worker/flang-aarch64-sharedlibs/build/lib && :
/usr/bin/ld: tools/clang/tools/clang-sycl-linker/CMakeFiles/clang-sycl-linker.dir/ClangSYCLLinker.cpp.o: undefined reference to symbol '_ZN4llvm6TripleC1ERKNS_5TwineE'
/usr/bin/ld: /home/tcwg-buildbot/worker/flang-aarch64-sharedlibs/build/./lib/libLLVMTargetParser.so.20.0git: error adding symbols: DSO missing from command line
clang++: error: linker command failed with exit code 1 (use -v to see invocation)
770.409 [1156/7/6299] Generating ../../../../share/scan-view/Reporter.py
770.413 [1156/6/6300] Linking CXX shared library lib/libclangSerialization.so.20.0git
770.421 [1156/5/6301] Generating ../../../../share/scan-view/bugcatcher.ico
770.422 [1156/4/6302] Generating ../../../../share/scan-view/ScanView.py
770.565 [1156/3/6303] Building CXX object tools/clang/tools/arcmt-test/CMakeFiles/arcmt-test.dir/arcmt-test.cpp.o
770.661 [1156/2/6304] Building CXX object tools/clang/tools/clang-check/CMakeFiles/clang-check.dir/ClangCheck.cpp.o
778.026 [1156/1/6305] Linking CXX shared library lib/libclang-cpp.so.20.0git
ninja: build stopped: subcommand failed.

```

</details>

https://github.com/llvm/llvm-project/pull/112245