[llvm] [PowerPC] Update DMF VSX ACC data transfer instructions (PR #138897)

[Lei Huang via llvm-commits]

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@@ -20,6 +20,8 @@ def sub_64 : SubRegIndex<64>;
 def sub_64_hi_phony : SubRegIndex<64,64>;
 def sub_vsx0 : SubRegIndex<128>;
 def sub_vsx1 : SubRegIndex<128, 128>;
+def sub_vsx2 : ComposedSubRegIndex<sub_vsx1, sub_vsx0>;
+def sub_vsx3 : ComposedSubRegIndex<sub_vsx2, sub_vsx0>;
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lei137 wrote:

These are not part of this PR and I will remove them.

https://github.com/llvm/llvm-project/pull/138897