[llvm] [AMDGPU] Add intrinsics and MIs for ds_bvh_stack_* (PR #130007)

[Jay Foad via llvm-commits]

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@@ -258,10 +258,13 @@ multiclass DS_1A2D_Off8_RET_mc<string opName,
   }
 }
 
-class DS_BVH_STACK<string opName>
+class DS_BVH_STACK<string opName,
+                   RegisterClass rc,
+                   RegisterClass src>
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jayfoad wrote:

Nit: call them `vdst_rc` and `data1_rc`?

https://github.com/llvm/llvm-project/pull/130007