[RISCV] Make vsetvli in test not loop invariant. NFC

The middle end will remove the inner vsetvli otherwise, and it's more typical to set the AVL to the remaining VL.

This also prevents the test from showing up as a regression in #91319

Author: lukel97

llvm/test/CodeGen/RISCV/rvv/vsetvli-insert.ll

@@ -102,23 +102,23 @@ declare <vscale x 1 x i1> @llvm.riscv.vmand.nxv1i1.i64(<vscale x 1 x i1>, <vscal
 define void @test6(ptr nocapture readonly %A, ptr nocapture %B, i64 %n) {
 ; CHECK-LABEL: test6:
 ; CHECK:       # %bb.0: # %entry
-; CHECK-NEXT:    vsetvli a6, a2, e32, m1, ta, ma
-; CHECK-NEXT:    beqz a6, .LBB5_3
+; CHECK-NEXT:    vsetvli a2, a2, e32, m1, ta, ma
+; CHECK-NEXT:    beqz a2, .LBB5_3
 ; CHECK-NEXT:  # %bb.1: # %for.body.preheader
-; CHECK-NEXT:    li a4, 0
+; CHECK-NEXT:    li a3, 0
 ; CHECK-NEXT:  .LBB5_2: # %for.body
 ; CHECK-NEXT:    # =>This Inner Loop Header: Depth=1
-; CHECK-NEXT:    slli a3, a4, 2
-; CHECK-NEXT:    add a5, a0, a3
+; CHECK-NEXT:    slli a4, a3, 2
+; CHECK-NEXT:    add a5, a0, a4
 ; CHECK-NEXT:    vle32.v v8, (a5)
 ; CHECK-NEXT:    vmsle.vi v9, v8, -3
 ; CHECK-NEXT:    vmsgt.vi v10, v8, 2
 ; CHECK-NEXT:    vmor.mm v0, v9, v10
-; CHECK-NEXT:    add a3, a3, a1
-; CHECK-NEXT:    vse32.v v8, (a3), v0.t
-; CHECK-NEXT:    add a4, a4, a6
-; CHECK-NEXT:    vsetvli a6, a2, e32, m1, ta, ma
-; CHECK-NEXT:    bnez a6, .LBB5_2
+; CHECK-NEXT:    add a4, a4, a1
+; CHECK-NEXT:    vse32.v v8, (a4), v0.t
+; CHECK-NEXT:    add a3, a3, a2
+; CHECK-NEXT:    vsetvli a2, a2, e32, m1, ta, ma
+; CHECK-NEXT:    bnez a2, .LBB5_2
 ; CHECK-NEXT:  .LBB5_3: # %for.cond.cleanup
 ; CHECK-NEXT:    ret
 entry:
@@ -142,7 +142,7 @@ for.body:                                         ; preds = %entry, %for.body
   %7 = bitcast ptr %add.ptr1 to ptr
   tail call void @llvm.riscv.vse.mask.nxv2i32.i64(<vscale x 2 x i32> %3, ptr %7, <vscale x 2 x i1> %6, i64 %1)
   %add = add i64 %1, %i.012
-  %8 = tail call i64 @llvm.riscv.vsetvli.i64(i64 %n, i64 2, i64 0)
+  %8 = tail call i64 @llvm.riscv.vsetvli.i64(i64 %1, i64 2, i64 0)
   %cmp.not = icmp eq i64 %8, 0
   br i1 %cmp.not, label %for.cond.cleanup, label %for.body
 }