Revert "[IRSim] Adding basic implementation of llvm-sim."

This reverts commit 15645d0.

Author: AndrewLitteken

llvm/test/tools/llvm-sim/Inputs/sim1.ll

@@ -51,7 +51,6 @@ subdirectories =
  llvm-rc
  llvm-reduce
  llvm-rtdyld
- llvm-sim
  llvm-size
  llvm-split
  llvm-undname