Revert r68708. It was causing this failure in the self-hosting buildbot:

llvm[2]: Compiling lto.cpp for Debug build  (PIC)
make[2]: *** No rule to make target `/Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.sh.build/Debug/lib/libLLVMBitWriter.a', needed by `/Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.sh.build/Release/lib/libLTO.dylib'.  Stop.
make[1]: *** [all] Error 1
make: *** [all] Error 1

llvm-svn: 68721