[RISCV] Fix a typo in fixed_m1_in_m2_tail test [nfc]

When I added these, they were supposed to be sub-vector inserts, but since
I got a couple index values wrong, they were instead general shuffles.

Author: preames

llvm/test/Analysis/CostModel/RISCV/shuffle-insert_subvector.ll

@@ -573,16 +573,16 @@ define void @fixed_m2_in_m4_notail(<8 x i64> %src, <8 x i64> %passthru) vscale_r
 
 define void @fixed_m1_in_m2_tail(<8 x i32> %src, <8 x i32> %passthru) vscale_range(2) {
 ; CHECK-LABEL: 'fixed_m1_in_m2_tail'
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 19 for instruction: %1 = shufflevector <8 x i32> %src, <8 x i32> %passthru, <8 x i32> <i32 8, i32 9, i32 10, i32 4, i32 4, i32 5, i32 6, i32 8>
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 11 for instruction: %2 = shufflevector <8 x i32> %src, <8 x i32> %passthru, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 8, i32 8, i32 10, i32 7>
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %1 = shufflevector <8 x i32> %src, <8 x i32> %passthru, <8 x i32> <i32 8, i32 9, i32 10, i32 3, i32 4, i32 5, i32 6, i32 7>
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %2 = shufflevector <8 x i32> %src, <8 x i32> %passthru, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 8, i32 9, i32 10, i32 7>
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret void
 ;
 ; SIZE-LABEL: 'fixed_m1_in_m2_tail'
-; SIZE-NEXT:  Cost Model: Found an estimated cost of 11 for instruction: %1 = shufflevector <8 x i32> %src, <8 x i32> %passthru, <8 x i32> <i32 8, i32 9, i32 10, i32 4, i32 4, i32 5, i32 6, i32 8>
-; SIZE-NEXT:  Cost Model: Found an estimated cost of 11 for instruction: %2 = shufflevector <8 x i32> %src, <8 x i32> %passthru, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 8, i32 8, i32 10, i32 7>
+; SIZE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %1 = shufflevector <8 x i32> %src, <8 x i32> %passthru, <8 x i32> <i32 8, i32 9, i32 10, i32 3, i32 4, i32 5, i32 6, i32 7>
+; SIZE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %2 = shufflevector <8 x i32> %src, <8 x i32> %passthru, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 8, i32 9, i32 10, i32 7>
 ; SIZE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: ret void
 ;
-  shufflevector <8 x i32> %src, <8 x i32> %passthru, <8 x i32> <i32 8, i32 9, i32 10, i32 4, i32 4, i32 5, i32 6, i32 8>
-  shufflevector <8 x i32> %src, <8 x i32> %passthru, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 8, i32 8, i32 10, i32 7>
+  shufflevector <8 x i32> %src, <8 x i32> %passthru, <8 x i32> <i32 8, i32 9, i32 10, i32 3, i32 4, i32 5, i32 6, i32 7>
+  shufflevector <8 x i32> %src, <8 x i32> %passthru, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 8, i32 9, i32 10, i32 7>
   ret void
 }