[flang] Add 32-bit AIX target specific in order to build 32-bit flang-rt#136051

DanielCChen merged 2 commits intollvm:mainllvm/llvm-project:mainfrom

DanielCChen:daniel_32bit_aix_targetDanielCChen/llvm-project:daniel_32bit_aix_targetCopy head branch name to clipboard