[llvm] RuntimeLibcalls: Remove darwin override of half convert libcalls (PR #148782)

[LLVM Continuous Integration via llvm-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 `llvm` at step 6 "test".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/162/builds/28201

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

```
Step 6 (test) failure: build (failure)
...
PASS: lldb-unit :: Host/./HostTests/75/125 (259 of 3128)
PASS: lldb-api :: functionalities/lazy-loading/TestLazyLoading.py (260 of 3128)
PASS: lldb-api :: functionalities/tail_call_frames/thread_step_out_message/TestArtificialFrameStepOutMessage.py (261 of 3128)
PASS: lldb-api :: types/TestIntegerType.py (262 of 3128)
PASS: lldb-api :: functionalities/tail_call_frames/disambiguate_tail_call_seq/TestDisambiguateTailCallSeq.py (263 of 3128)
PASS: lldb-api :: functionalities/exec/TestExec.py (264 of 3128)
PASS: lldb-api :: functionalities/data-formatter/data-formatter-stl/libcxx-simulators/unique_ptr/TestDataFormatterLibcxxUniquePtrSimulator.py (265 of 3128)
PASS: lldb-api :: python_api/type/TestTypeList.py (266 of 3128)
PASS: lldb-api :: functionalities/thread/concurrent_events/TestConcurrentManyBreakpoints.py (267 of 3128)
PASS: lldb-api :: functionalities/tail_call_frames/disambiguate_paths_to_common_sink/TestDisambiguatePathsToCommonSink.py (268 of 3128)
FAIL: lldb-api :: tools/lldb-dap/output/TestDAP_output.py (269 of 3128)
******************** TEST 'lldb-api :: tools/lldb-dap/output/TestDAP_output.py' FAILED ********************
Script:
--
/usr/bin/python3 /home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/API/dotest.py -u CXXFLAGS -u CFLAGS --env LLVM_LIBS_DIR=/home/worker/2.0.1/lldb-x86_64-debian/build/./lib --env LLVM_INCLUDE_DIR=/home/worker/2.0.1/lldb-x86_64-debian/build/include --env LLVM_TOOLS_DIR=/home/worker/2.0.1/lldb-x86_64-debian/build/./bin --arch x86_64 --build-dir /home/worker/2.0.1/lldb-x86_64-debian/build/lldb-test-build.noindex --lldb-module-cache-dir /home/worker/2.0.1/lldb-x86_64-debian/build/lldb-test-build.noindex/module-cache-lldb/lldb-api --clang-module-cache-dir /home/worker/2.0.1/lldb-x86_64-debian/build/lldb-test-build.noindex/module-cache-clang/lldb-api --executable /home/worker/2.0.1/lldb-x86_64-debian/build/./bin/lldb --compiler /home/worker/2.0.1/lldb-x86_64-debian/build/./bin/clang --dsymutil /home/worker/2.0.1/lldb-x86_64-debian/build/./bin/dsymutil --make /usr/bin/gmake --llvm-tools-dir /home/worker/2.0.1/lldb-x86_64-debian/build/./bin --lldb-obj-root /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb --lldb-libs-dir /home/worker/2.0.1/lldb-x86_64-debian/build/./lib --cmake-build-type Release -t /home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/API/tools/lldb-dap/output -p TestDAP_output.py
--
Exit Code: 1

Command Output (stdout):
--
lldb version 22.0.0git (https://github.com/llvm/llvm-project.git revision 5b528a1041fb6b64e5722f1bc600eb0617118a3e)
  clang revision 5b528a1041fb6b64e5722f1bc600eb0617118a3e
  llvm revision 5b528a1041fb6b64e5722f1bc600eb0617118a3e
Skipping the following test categories: ['libc++', 'msvcstl', 'dsym', 'gmodules', 'debugserver', 'objc']

--
Command Output (stderr):
--
Change dir to: /home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/API/tools/lldb-dap/output
runCmd: settings clear --all

output: 

runCmd: settings set symbols.enable-external-lookup false

output: 

runCmd: settings set target.inherit-tcc true

output: 

runCmd: settings set target.disable-aslr false

output: 

runCmd: settings set target.detach-on-error false

output: 


```

</details>

https://github.com/llvm/llvm-project/pull/148782