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

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-cmake-x86_64-avx512-linux` running on `avx512-intel64` while building `llvm` at step 7 "ninja check 1".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/133/builds/17048

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 7 (ninja check 1) failure: stage 1 checked (failure)
******************** TEST 'LLVM :: Transforms/OpenMP/spmdization_guarding.ll' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
/localdisk2/buildbot/llvm-worker/clang-cmake-x86_64-avx512-linux/stage1/bin/opt -S -passes=openmp-opt < /localdisk2/buildbot/llvm-worker/clang-cmake-x86_64-avx512-linux/llvm/llvm/test/Transforms/OpenMP/spmdization_guarding.ll | /localdisk2/buildbot/llvm-worker/clang-cmake-x86_64-avx512-linux/stage1/bin/FileCheck /localdisk2/buildbot/llvm-worker/clang-cmake-x86_64-avx512-linux/llvm/llvm/test/Transforms/OpenMP/spmdization_guarding.ll # RUN: at line 2
+ /localdisk2/buildbot/llvm-worker/clang-cmake-x86_64-avx512-linux/stage1/bin/opt -S -passes=openmp-opt
+ /localdisk2/buildbot/llvm-worker/clang-cmake-x86_64-avx512-linux/stage1/bin/FileCheck /localdisk2/buildbot/llvm-worker/clang-cmake-x86_64-avx512-linux/llvm/llvm/test/Transforms/OpenMP/spmdization_guarding.ll
/localdisk2/buildbot/llvm-worker/clang-cmake-x86_64-avx512-linux/stage1/bin/opt: WARNING: failed to create target machine for 'nvptx64': unable to get target for 'nvptx64', see --version and --triple.
/localdisk2/buildbot/llvm-worker/clang-cmake-x86_64-avx512-linux/llvm/llvm/test/Transforms/OpenMP/spmdization_guarding.ll:88:15: error: CHECK-NEXT: expected string not found in input
; CHECK-NEXT: [[TMP4:%.*]] = addrspacecast ptr [[ARRAYIDX1_I]] to ptr addrspace(1)
              ^
<stdin>:44:43: note: scanning from here
 store i32 0, ptr %x, align 4, !noalias !7
                                          ^
<stdin>:44:43: note: with "ARRAYIDX1_I" equal to "%arrayidx1\\.i"
 store i32 0, ptr %x, align 4, !noalias !7
                                          ^
<stdin>:62:23: note: possible intended match here
 %sub.i = add nsw i32 %N.addr.sroa.0.0.extract.trunc, -1
                      ^
/localdisk2/buildbot/llvm-worker/clang-cmake-x86_64-avx512-linux/llvm/llvm/test/Transforms/OpenMP/spmdization_guarding.ll:444:24: error: undefined variable: ATTR9
; CHECK: attributes #[[ATTR9]] = { nounwind willreturn "llvm.assume"="omp_no_openmp,ompx_spmd_amenable" }
                       ^
<stdin>:226:1: note: possible intended match here
attributes #9 = { nounwind willreturn "llvm.assume"="omp_no_openmp,ompx_spmd_amenable" }
^

Input file: <stdin>
Check file: /localdisk2/buildbot/llvm-worker/clang-cmake-x86_64-avx512-linux/llvm/llvm/test/Transforms/OpenMP/spmdization_guarding.ll

-dump-input=help explains the following input dump.

Input was:
<<<<<<
             .
             .
             .
            39:  %2 = call i32 @__kmpc_get_hardware_thread_id_in_block() 
            40:  %3 = icmp eq i32 %2, 0 
            41:  br i1 %3, label %region.guarded, label %region.barrier 
            42:  
            43: region.guarded: ; preds = %region.check.tid 
            44:  store i32 0, ptr %x, align 4, !noalias !7 
next:88'0                                                 X error: no match found
next:88'1                                                   with "ARRAYIDX1_I" equal to "%arrayidx1\\.i"
            45:  store i32 1, ptr %arrayidx1.i, align 4, !noalias !7 
next:88'0       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            46:  store i32 %N.addr.sroa.0.0.extract.trunc, ptr %arrayidx2.i, align 4, !noalias !7 
next:88'0       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
...

```

</details>

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