nfsd: Add errno mapping for EREMOTEIO

The NFS client can occasionally return EREMOTEIO when signalling issues
with the server.  ...map to NFSERR_IO.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Author: Jeff Layton

fs/nfsd/nfsproc.c

@@ -874,6 +874,7 @@ nfserrno (int errno)
 		{ nfserr_toosmall, -ETOOSMALL },
 		{ nfserr_serverfault, -ESERVERFAULT },
 		{ nfserr_serverfault, -ENFILE },
+		{ nfserr_io, -EREMOTEIO },
 		{ nfserr_io, -EUCLEAN },
 		{ nfserr_perm, -ENOKEY },
 		{ nfserr_no_grace, -ENOGRACE},