[llvm] [RISCV][NFC] Use !range bang operator (PR #66494)

[Wang Pengcheng via llvm-commits]

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@@ -416,12 +416,11 @@ class VRegList<list<dag> LIn, int start, int nf, int lmul, bit isV0> {
 }
 
 // Vector registers
-foreach Index = 0-31 in {
+foreach Index = !range(0, 32, 1) in {
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wangpc-pp wrote:

It's not better, just to align other `foreach`s below. It may be more uniformed from the style perspertive.

https://github.com/llvm/llvm-project/pull/66494