[compiler-rt] [compiler-rt] Add CMake option to enable execute-only code generation on AArch64 (PR #140555)

[Csanád Hajdú via llvm-commits]

Il-Capitano wrote:

I simplified the configuration based on the discussion in the RFC. C and C++ compiler flags will be handled by the change in https://github.com/llvm/llvm-project/pull/143698.

https://github.com/llvm/llvm-project/pull/140555