[clang] [llvm] [AIX] Add -msave-reg-params to save arguments to stack (PR #97524)

[Qiu Chaofan via cfe-commits]

ecnelises wrote:

Thanks for pointing LTO stuff out.   Do you mean the module flags might be messed up when merging in LTO? I thought a file level codegen option can be mapped to a module level flag.

https://github.com/llvm/llvm-project/pull/97524