MCJIT: Tidy up the constructor.

The MCJIT doesn't need or want a TargetJITInfo. That's vestigal from the old
JIT, so just remove it.

rdar://12119347

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162280 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed