tools/genromfs.c: Improve check for empty directories. If the directory...

tools/genromfs.c:  Improve check for empty directories.  If the directory contains only unsupported, special files, then it is still empty.  Fix some collection of statistics that was cause statfs() to return some incorrect values.  Add logic to handle the case where the host and the target differ in endian-ness.  fs/procfs:  In show mountpoints, add support so that the CROMFS file system type is recognized.