[llvm] [AMDGPU] Make `getAssumedAddrSpace` return AS1 for pointer kernel arguments (PR #137488)

[Matt Arsenault via llvm-commits]

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@@ -4,14 +4,24 @@
 define amdgpu_kernel void @flat_atomic_fadd_f32_noret_pat(ptr %ptr) {
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arsenm wrote:

This is breaking the purpose of the test 

https://github.com/llvm/llvm-project/pull/137488