Revert "[IR] Move optional data in llvm::Function into a hungoff uselist"

This reverts commit r256090.

This broke llvm-clang-lld-x86_64-debian-fast.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256091 91177308-0d34-0410-b5e6-96231b3b80d8
8 files changed