(current_minor_maps): Fixed resizing of cmm_maps;

(current_minor_maps): Fixed resizing of cmm_maps;
only update cmm_size if realloc actually succeeds.
Testing with initial size of 2 elements revealed that using
realloc on GNU/Linux would cause a random trap in xmalloc
later on, so I rewrote the code to use malloc/bcopy/free instead
of realloc.