[PATCH] knfsd: fixing missing 'expkey' support for fsid type 3

Type '3' is used for the fsid in filehandles when the device number of the
device holding the filesystem has more than 8 bits in either major or minor.
Unfortunately expkey_parse doesn't recognise type 3.  Fix this.

(Slighty modified from Frank's original)

Signed-off-by: Frank Filz <ffilzlnx@us.ibm.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>