nfsd: handle EUCLEAN

Eric Sandeen reports that xfs can return this if filesystem corruption
prevented completing the operation.

Reported-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c
index a56ee10..78cd770 100644
--- a/fs/nfsd/nfsproc.c
+++ b/fs/nfsd/nfsproc.c
@@ -791,6 +791,7 @@
 		{ nfserr_toosmall, -ETOOSMALL },
 		{ nfserr_serverfault, -ESERVERFAULT },
 		{ nfserr_serverfault, -ENFILE },
+		{ nfserr_io, -EUCLEAN },
 	};
 	int	i;