Temporarily revert r68552. This was causing a failure in the self-hosting LLVM

Temporarily revert r68552. This was causing a failure in the self-hosting LLVM
builds.

--- Reverse-merging (from foreign repository) r68552 into '.':
U    test/CodeGen/X86/tls8.ll
U    test/CodeGen/X86/tls10.ll
U    test/CodeGen/X86/tls2.ll
U    test/CodeGen/X86/tls6.ll
U    lib/Target/X86/X86Instr64bit.td
U    lib/Target/X86/X86InstrSSE.td
U    lib/Target/X86/X86InstrInfo.td
U    lib/Target/X86/X86RegisterInfo.cpp
U    lib/Target/X86/X86ISelLowering.cpp
U    lib/Target/X86/X86CodeEmitter.cpp
U    lib/Target/X86/X86FastISel.cpp
U    lib/Target/X86/X86InstrInfo.h
U    lib/Target/X86/X86ISelDAGToDAG.cpp
U    lib/Target/X86/AsmPrinter/X86ATTAsmPrinter.cpp
U    lib/Target/X86/AsmPrinter/X86IntelAsmPrinter.cpp
U    lib/Target/X86/AsmPrinter/X86ATTAsmPrinter.h
U    lib/Target/X86/AsmPrinter/X86IntelAsmPrinter.h
U    lib/Target/X86/X86ISelLowering.h
U    lib/Target/X86/X86InstrInfo.cpp
U    lib/Target/X86/X86InstrBuilder.h
U    lib/Target/X86/X86RegisterInfo.td

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68560 91177308-0d34-0410-b5e6-96231b3b80d8