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

[Stefan Pintilie via cfe-commits]

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@@ -80,6 +80,7 @@ class LLVM_LIBRARY_VISIBILITY PPCTargetInfo : public TargetInfo {
   bool IsISA3_0 = false;
   bool IsISA3_1 = false;
   bool HasQuadwordAtomics = false;
+  bool FullRegisterNames = false;
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stefanp-ibm wrote:

I did take a look at trying to do it this way at first but I was concerned that the option I wanted to add was target specific and I didn't want to add an option to `MCAsmInfo.h` that was only for PPC. However, I've taken a look at the existing options in there and it seems that there are already a set of options that are specific to one target or another so I'll try this approach.

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