More or less.
This is a bit of an experiment (which seems to work nicely) in that qfcc
and pak are build natively in one build tree, then the full system is
cross-built in another tree using the natively build qfcc and pak. Both
trees are created by cross-configure.sh as sub-directories of the current
directory. However, cross-configure.sh still assumes it is being run in a
subdirectory of the main quakeforge directory.
cross-make.sh checks if the native tree is in the current directory and if
so, builds it, otherwise it just runs make for the cross-build tree (this
allows for running cross-make in a sub-directory for things like sorting
out build issues).
