cmake: Fix MSVCRT override

Fix the CMake code that overrides the /MD flag with the /MT flag for
the Windows demo and loader projects.  The CMake debug and release
variables were set to /MTd and /MT, overriding all existing debug
and release settings.

Now replacing /MD with /MT in the debug and release variables,
without losing other debug/release settings.  Also performing
the MD/MT substitution for all release and debug configurations.

Change-Id: Id4a57c38bde0d909a95e7a49d9867029829e2c61
1 file changed