[llvm] [UnitTests] Fix shared build. NFC (PR #195906)

[via llvm-commits]

darkbuck wrote:

> This change is incorrect and breaks MinGW/Cygwin dylib builds.
> 
> ```
> FAILED: [code=1] unittests/DWARFLinkerParallel/DWARFLinkerParallelTests.exe 
>   : && /opt/w/llvm-stage1/bin/clang++ -O3 -DNDEBUG -Wno-profile-instr-unprofiled -Wno-profile-instr-out-of-date -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual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 -Wno-pass-failed -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -fprofile-instr-use="/opt/w/cygwin-instr.profdata" -Xclang -fno-pch-timestamp -O3 -DNDEBUG -Wl,--enable-auto-import -fuse-ld=lld -fprofile-instr-use="/opt/w/cygwin-instr.profdata"  -Wl,--gc-sections  -Xlinker --stack -Xlinker 16777216 unittests/DWARFLinkerParallel/CMakeFiles/DWARFLinkerParallelTests.dir/DWARFLinkerTest.cpp.o unittests/DWARFLinkerParallel/CMakeFiles/DWARFLinkerParallelTests.dir/StringPoolTest.cpp.o -o unittests/DWARFLinkerParallel/DWARFLinkerParallelTests.exe -Wl,--out-implib,unittests/DWARFLinkerParallel/libDWARFLinkerParallelTests.exe.a -Wl,--major-image-version,0,--minor-image-version,0  lib/libllvm_gtest_main.a  lib/libllvm_gtest.a  lib/libLLVMTestingSupport.a  lib/libLLVMDebugInfoDWARF.a  lib/libLLVM-23git.dll.a  -lpthread  lib/libLLVMObject.a  lib/libLLVMIRReader.a  lib/libLLVMBitReader.a  lib/libLLVMAsmParser.a  lib/libLLVMCore.a  lib/libLLVMRemarks.a  lib/libLLVMBitstreamReader.a  lib/libLLVMMCParser.a  lib/libLLVMMC.a  lib/libLLVMDebugInfoDWARFLowLevel.a  lib/libLLVMTextAPI.a  lib/libLLVMBinaryFormat.a  lib/libLLVMTargetParser.a  lib/libLLVMSupport.a  -lrt  -ldl  -lm  /usr/lib/libz.dll.a  /usr/lib/libzstd.dll.a  lib/libLLVMDemangle.a && :
>   ld.lld: error: duplicate symbol: llvm::raw_ostream::flush_nonempty()
>   >>> defined at libLLVMSupport.a(raw_ostream.cpp.o)
>   >>> defined at libLLVM-23git.dll.a(cygLLVM-23git.dll)
>   
>   ld.lld: error: duplicate symbol: llvm::raw_ostream::changeColor(llvm::raw_ostream::Colors, bool, bool)
>   >>> defined at libLLVMSupport.a(raw_ostream.cpp.o)
>   >>> defined at libLLVM-23git.dll.a(cygLLVM-23git.dll)
>   
>  (snip)
> ```
> 
> The proper fix has already been merged: #195902 .
> 
> Could you revert this?
> 
> cc: @JDevlieghere

done in #196215 

https://github.com/llvm/llvm-project/pull/195906