[clang] [llvm] Reland "[AArch64] Decouple feature dependency expansion. (#94279)" (PR #95519)

[David Green via cfe-commits]

davemgreen wrote:

GCC seems to work the same way, where the -march option takes precedence: https://godbolt.org/z/4vd13P5xx.

https://github.com/llvm/llvm-project/pull/95519