[llvm] [RISCV] Partially move doPeepholeMaskedRVV into RISCVFoldMasks (PR #72441)

[Craig Topper via llvm-commits]

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@@ -18,6 +18,7 @@
 
 #include "RISCV.h"
 #include "RISCVSubtarget.h"
+#include "RISCVISelDAGToDAG.h"
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topperc wrote:

Alphabetize? Though I'm surprised a SelectionDAG header is needed in an MIR pass.

https://github.com/llvm/llvm-project/pull/72441