[llvm] [AMDGPU][GlobalISel] Align `selectVOP3PMadMixModsImpl` with the `SelectionDAG` counterpart (PR #110168)

[Matt Arsenault via llvm-commits]

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@@ -73,10 +73,14 @@ define amdgpu_vs <5 x float> @test_5xf16_5xf32_add_ext_mul(<5 x half> inreg %x,
 ; GFX10-FAST-DENORM-NEXT:    v_mov_b32_e32 v2, s8
 ; GFX10-FAST-DENORM-NEXT:    v_mov_b32_e32 v3, s9
 ; GFX10-FAST-DENORM-NEXT:    v_mov_b32_e32 v4, s10
+; GFX10-FAST-DENORM-NEXT:    s_lshr_b32 s11, s0, 16
+; GFX10-FAST-DENORM-NEXT:    s_lshr_b32 s12, s1, 16
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arsenm wrote:

This regressed gfx10 which has the more relaxed constant bus limit 

https://github.com/llvm/llvm-project/pull/110168