[clang] [HIP] Replace use of `llvm-mc` with `clang` (PR #112041)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-ppc64le-rhel` running on `ppc64le-clang-rhel-test` while building `clang` at step 5 "build-unified-tree".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/145/builds/2444

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

```
Step 5 (build-unified-tree) failure: build (failure)
1.541 [501/4/1] Building CXX object tools/llvm-config/CMakeFiles/llvm-config.dir/llvm-config.cpp.o
1.579 [500/4/2] Linking CXX executable bin/llvm-config
1.589 [500/3/3] Generating VCSRevision.h
1.622 [497/5/4] Generating VCSVersion.inc
2.746 [496/5/5] Building CXX object tools/clang/lib/Basic/CMakeFiles/obj.clangBasic.dir/Version.cpp.o
5.810 [496/4/6] Building CXX object tools/clang/lib/Driver/CMakeFiles/obj.clangDriver.dir/ToolChains/HIPUtility.cpp.o
FAILED: tools/clang/lib/Driver/CMakeFiles/obj.clangDriver.dir/ToolChains/HIPUtility.cpp.o 
ccache /home/docker/llvm-external-buildbots/clang.17.0.6/bin/clang++ --gcc-toolchain=/gcc-toolchain/usr -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/tools/clang/lib/Driver -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/lib/Driver -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/tools/clang/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror -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 -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -MD -MT tools/clang/lib/Driver/CMakeFiles/obj.clangDriver.dir/ToolChains/HIPUtility.cpp.o -MF tools/clang/lib/Driver/CMakeFiles/obj.clangDriver.dir/ToolChains/HIPUtility.cpp.o.d -o tools/clang/lib/Driver/CMakeFiles/obj.clangDriver.dir/ToolChains/HIPUtility.cpp.o -c /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/lib/Driver/ToolChains/HIPUtility.cpp
/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/lib/Driver/ToolChains/HIPUtility.cpp:343:20: error: unused variable 'TC' [-Werror,-Wunused-variable]
  343 |   const ToolChain &TC = T.getToolChain();
      |                    ^~
1 error generated.
6.440 [496/3/7] Building CXX object lib/Object/CMakeFiles/LLVMObject.dir/IRSymtab.cpp.o
21.581 [496/2/8] Building CXX object lib/CodeGen/AsmPrinter/CMakeFiles/LLVMAsmPrinter.dir/AsmPrinter.cpp.o
23.783 [496/1/9] Building CXX object lib/LTO/CMakeFiles/LLVMLTO.dir/LTO.cpp.o
ninja: build stopped: subcommand failed.

```

</details>

https://github.com/llvm/llvm-project/pull/112041