[X86] Support EGPR for inline assembly. (#92338)

"jR": explicitly enables EGPR
"r", "l", "q": enables/disables EGPR w/wo -mapx-inline-asm-use-gpr32
"jr": explicitly enables GPR with -mapx-inline-a

[X86] Support EGPR for inline assembly. (#92338)

"jR": explicitly enables EGPR
"r", "l", "q": enables/disables EGPR w/wo -mapx-inline-asm-use-gpr32
"jr": explicitly enables GPR with -mapx-inline-asm-use-gpr32
-mapx-inline-asm-use-gpr32 will also define a new macro:
`__APX_INLINE_ASM_USE_GPR32__`

GCC patches:
https://gcc.gnu.org/pipermail/gcc-patches/2023-September/631183.html
https://gcc.gnu.org/pipermail/gcc-patches/2023-September/631186.html
[[PATCH v2] x86: Define _APX_INLINE_ASM_USE_GPR32_
(gnu.org)](https://gcc.gnu.org/pipermail/gcc-patches/2024-April/649003.html)

Reference: https://gcc.godbolt.org/z/nPPvbY6r4

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