Apply r207674 from the clangbsd project branch:
Apply r207674 from the clangbsd project branch:

Make "clang -print-multi-os-directory" return "." on amd64, matching
gcc's behaviour.  This is needed because some ports use the option to
determine the installation directory for their libraries.

Requested by:	kwm
Approved by:	rpaulo (mentor)

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