Revert r206732 which is causing llc to crash on most of the build bots.

Original commit message:
  Implement builtins for safe division: safe.sdiv.iN, safe.udiv.iN,
  safe.srem.iN, safe.urem.iN (iN = i8, i61, i32, or i64).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206735 91177308-0d34-0410-b5e6-96231b3b80d8