[LowerMemIntrinsics] Use i8 GEPs in memcpy/memmove lowering#112707

ritter-x2a merged 2 commits intollvm:mainllvm/llvm-project:mainfrom

ritter-x2a:memintrinsic-i8-gepsritter-x2a/llvm-project:memintrinsic-i8-gepsCopy head branch name to clipboard