[llvm] [AMDGPU] Still set up the two SGPRs for queue ptr even it is COV5 (PR #112403)

[Shilei Tian via llvm-commits]

shiltian wrote:

yeah we have this issue the first day we support inreg SGPR argument (https://github.com/llvm/llvm-project/pull/67182) and at that moment COV5 was already the default so the issue was not exposed.

https://github.com/llvm/llvm-project/pull/112403