[RemoveDIs] Copy debug mode to new functions in amdgpu-lower-buffer-fat-pointers

Fixes failing tests after https://github.com/llvm/llvm-project/pull/84308

LLVM :: CodeGen/AMDGPU/GlobalISel/irtranslator-non-integral-address-spaces-vectors.ll
LLVM :: CodeGen/AMDGPU/GlobalISel/irtranslator-non-integral-address-spaces.ll
LLVM :: CodeGen/AMDGPU/lower-buffer-fat-pointers-calls.ll
LLVM :: CodeGen/AMDGPU/lower-buffer-fat-pointers-constants.ll
LLVM :: CodeGen/AMDGPU/lower-buffer-fat-pointers-pointer-ops.ll
LLVM :: CodeGen/AMDGPU/pal-metadata-3.0.ll

Buildbots: https://lab.llvm.org/buildbot/#/builders/121/builds/39855