[llvm] [GlobalISel] Use G_ANYEXT instead of G_ZEXT for shift amount widening (PR #223136)

[Matt Arsenault via llvm-commits]

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@@ -1307,10 +1307,14 @@ define i8 @combine_i8_sdiv_pow2(i8 %x) {
 ;
 ; CHECK-GI-LABEL: combine_i8_sdiv_pow2:
 ; CHECK-GI:       // %bb.0:
-; CHECK-GI-NEXT:    sbfx w8, w0, #7, #1
+; CHECK-GI-NEXT:    sxtb w8, w0
+; CHECK-GI-NEXT:    mov w9, #7 // =0x7
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arsenm wrote:

another regression 

https://github.com/llvm/llvm-project/pull/223136