Temporarily revert r65755. It was causing failures in the self-hosting

Temporarily revert r65755. It was causing failures in the self-hosting
testsuite:

Running /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvmCore/test/CodeGen/X86/dg.exp ...
FAIL: /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvmCore/test/CodeGen/X86/nancvt.ll
Failed with exit(1) at line 2
while running: grep 2147027116 nancvt.ll.tmp | count 3
count: expected 3 lines and got        0.
child process exited abnormally
FAIL: /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvmCore/test/CodeGen/X86/vec_ins_extract.ll
Failed with exit(1) at line 1
while running:  llvm-as < /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvmCore/test/CodeGen/X86/vec_ins_extract.ll |  opt -scalarrepl -instcombine |   llc -march=x86 -mcpu=yonah | not /usr/bin/grep sub.*esp
      subl      $28, %esp
      subl      $28, %esp
child process exited abnormally

And more.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65758 91177308-0d34-0410-b5e6-96231b3b80d8