[PATCH] knfsd: nfsd4: handling more nfsd_cross_mnt errors in nfsd4 readdir

This patch on its own causes no change in behavior, since nfsd_cross_mnt()
only returns -EAGAIN; but in the future I'd like it to also be able to return
-ETIMEDOUT, so we may as well handle any possible error here.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>