[clang] [llvm] [PowerPC] Add an alias for -mregnames so that full register names used in assembly. (PR #70255)

[Fangrui Song via cfe-commits]

================
@@ -5011,6 +5011,12 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     Args.AddLastArg(CmdArgs, options::OPT_fthinlto_index_EQ);
   }
 
+  if (const Arg *A =
+          Args.getLastArg(options::OPT_mregnames, options::OPT_mno_regnames)) {
----------------
MaskRay wrote:

This will make other targets accept the ppc-specific -mregnames

https://github.com/llvm/llvm-project/pull/70255