This allows people to use the base directory of cross-compiled
dependencies (typically our dependencies.zip file), rather than always
having to specify the actual include directory.
Fixes issues using DepsPath(32|64), was using ${lib_suffix} instead of
${_lib_suffix} so 32/64-sepcific directories wouldn't work properly.
Also the DepsPath environment/cmake variable wasn't specified for the
library search.
Also added the same dependency search paths for libfdk (if someone wants
to use it on windows for whatever reason)
I actually did this because it makes it a bit easier to use with a
build from cross-compiled windows FFMpeg/x264 DLLs. When compiling on
linux I just have it compile to a custom prefix directory for the
specific windows arch, then I just copy the arch dir back to my windows
HD when complete. Adding this to the cmake allows me to use the compile
arch directories directly without modification.
This can make it a bit easier to set up 32bit/64bit environments
separately on windows. This simply allows you to additionally set
FFmpegPath32, FFmpegPath64, x264Path32, x264Path64, etc.
