Pull in r164717 from upstream clang trunk:
Pull in r164717 from upstream clang trunk:

  Allow -MF to be used in combination with -E -M or -E -MM.

This should help with building the lang/ghc port.

MFC after:	1 week

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase