[clang] [clang-tools-extra] [llvm] [clang][headers] Need a way for math.h to share the definitions of INIFINITY and NAN with float.h (PR #164348)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-ppc64le-linux-multistage` running on `ppc64le-clang-multistage-test` while building `clang-tools-extra,clang,llvm` at step 5 "ninja check 1".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/76/builds/13285

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

```
Step 5 (ninja check 1) failure: 1200 seconds without output running [b'ninja', b'check-all'], attempting to kill
...
[78/85] Generating POWERPC64LELinuxConfig/Asan-powerpc64le-calls-Noinst-Test
[79/85] Generating POWERPC64LELinuxConfig/Asan-powerpc64le-inline-Noinst-Test
[80/85] Generating ASAN_INST_TEST_OBJECTS.gtest-all.cc.powerpc64le-calls.o
[81/85] Generating POWERPC64LELinuxDynamicConfig/Asan-powerpc64le-calls-Dynamic-Test
[82/85] Generating POWERPC64LELinuxConfig/Asan-powerpc64le-calls-Test
[83/85] Generating ASAN_INST_TEST_OBJECTS.gtest-all.cc.powerpc64le-inline.o
[84/85] Generating POWERPC64LELinuxDynamicConfig/Asan-powerpc64le-inline-Dynamic-Test
[85/85] Generating POWERPC64LELinuxConfig/Asan-powerpc64le-inline-Test
[1055/1277] No install step for 'runtimes'
[1057/1277] Completed 'runtimes'
command timed out: 1200 seconds without output running [b'ninja', b'check-all'], attempting to kill
process killed by signal 9
program finished with exit code -1
elapsedTime=1551.523747

```

</details>

https://github.com/llvm/llvm-project/pull/164348