Auto merge of #38055 - rkruppe:rm-unused-llvm-ffi, r=alexcrichton
Auto merge of #38055 - rkruppe:rm-unused-llvm-ffi, r=alexcrichton

Remove unused functions from rustc_llvm

GBGamer/rust,graydon/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust,aidancully/rust,GBGamer/rust,GBGamer/rust,graydon/rust,GBGamer/rust,graydon/rust,GBGamer/rust,aidancully/rust,graydon/rust,aidancully/rust