[clang] [Clang][AMDGPU] Add a builtin for llvm.amdgcn.make.buffer.rsrc intrinsic (PR #95276)

[Matt Arsenault via cfe-commits]

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@@ -33,6 +33,7 @@
 //  q -> Scalable vector, followed by the number of elements and the base type.
 //  Q -> target builtin type, followed by a character to distinguish the builtin type
 //    Qa -> AArch64 svcount_t builtin type.
+//    Qb -> AMDGPU __amdgpu_buffer_rsrc_t builtin type.
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arsenm wrote:

True it's not testable, but it still logically belongs with the definition of the type 

https://github.com/llvm/llvm-project/pull/95276