Revert "[compiler-rt][X86] Use functions in cpuid.h instead of inline assembly (#97877)"
This reverts commit 19cf8deabe1124831164987f1b9bf2f806c0a875.
This was causing quite a few buildbot failures (see the PR description).
Reverting for now while I have time to sort it out. Seems like it should
just be conditional preprocessor macros for X86 however.