[AMDGPU] gfx11 scalar memory instructions

Contributors:
Mirko Brkusanin <Mirko.Brkusanin@amd.com>

Patch 9/N for upstreaming of AMDGPU gfx11 architecture.

Depends on D125820

Reviewed By: kosarev, #amdgpu, arsenm

Differential Revision: https://reviews.llvm.org/D125822