[Attributor] Honor alloca address space also for Heap2Stack allocas

[jdoerfert]

The AMD gpu backend doesn't like AS0 allocas. We need to create them in the alloca AS instead. Causes OpenMP programs on AMD GPU to crash at compile time, sometimes with the weirdest assertions.

[llvmbot]

@llvm/issue-subscribers-openmp

[jdoerfert]

/cherry-pick 8ad39fb

[llvmbot]

Failed to cherry-pick: 8ad39fb

https://github.com/llvm/llvm-project/actions/runs/1855576025

Please manually backport the fix and push it to your github fork. Once this is done, please add a comment like this:

/branch <user>/<repo>/<branch>

[jdoerfert]

/cherry-pick 8ad39fb

[llvmbot]

/branch llvmbot/llvm-project/issue53858

[llvmbot]

/pull-request llvmbot#79