Fix a regression in the RXKAD security module introduced in:

	commit 91e916cf
	Author: Al Viro <viro@ftp.linux.org.uk>
	Date:   Sat Mar 29 03:08:38 2008 +0000

	net/rxrpc trivial annotations

A variable was declared as a 16-bit type rather than a 32-bit type.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-with-apologies-by: NAl Viro <viro@ZenIV.linux.org.uk>
Signed-of-by: NLinus Torvalds <torvalds@linux-foundation.org>