[llvm] [RISCV] Simplify mask operand check in VLOptimizer. NFC (PR #150373)

[Pengcheng Wang via llvm-commits]

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@@ -24,6 +24,7 @@ body:     |
     %0:vr = COPY $v8
     %1:vr = COPY $v9
     %2:gprnox0 = COPY $x10
-    renamable $v8 = PseudoVAADD_VV_MF8 undef $noreg, %0, %1, 0, %2, 3 /* e8 */, 0
+    %3:vr = PseudoVAADD_VV_MF8 undef $noreg, %0, %1, 0, %2, 3 /* e8 */, 0
+    $v8 = COPY %3
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wangpc-pp wrote:

This PR should be an NFC but where does this change come from?

https://github.com/llvm/llvm-project/pull/150373