[llvm] AMDGPU/GlobalISel: RegBankLegalize rules for cluster_load_b32/b64/b128 (PR #196186)

[Petar Avramovic via llvm-commits]

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@@ -1872,6 +1876,26 @@ RegBankLegalizeRules::RegBankLegalizeRules(const GCNSubtarget &_ST,
                     amdgcn_global_store_async_from_lds_b128})
       .Any({{}, {{}, {IntrId, VgprP1, VgprP3}}});
 
+  addRulesForIOpcs({amdgcn_cluster_load_b32})
+      .Any({{UniB32}, {{UniInVgprB32}, {IntrId, SgprP1, Imm, SgprB32_M0}}})
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petar-avramovic wrote:

```suggestion
      .Any({{UniB32}, {{UniInVgprB32}, {IntrId, VgprP1, Imm, SgprB32_M0}}})
```
Think that this is actually being selected, not sure if there is a reason to leave P1 arg in sgpr (inst select will insert copy)

https://github.com/llvm/llvm-project/pull/196186