NFSD: Add nfsd4_encode_fattr4_owner()

Refactor the encoder for FATTR4_OWNER into a helper. In a
subsequent patch, this helper will be called from a bitmask loop.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

fs/nfsd/nfs4xdr.c

@@ -3195,6 +3195,12 @@ static __be32 nfsd4_encode_fattr4_numlinks(struct xdr_stream *xdr,
 	return nfsd4_encode_uint32_t(xdr, args->stat.nlink);
 }
 
+static __be32 nfsd4_encode_fattr4_owner(struct xdr_stream *xdr,
+					const struct nfsd4_fattr_args *args)
+{
+	return nfsd4_encode_user(xdr, args->rqstp, args->stat.uid);
+}
+
 /*
  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
  * ourselves.
@@ -3489,8 +3495,8 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
 			goto out;
 	}
 	if (bmval1 & FATTR4_WORD1_OWNER) {
-		status = nfsd4_encode_user(xdr, rqstp, args.stat.uid);
-		if (status)
+		status = nfsd4_encode_fattr4_owner(xdr, &args);
+		if (status != nfs_ok)
 			goto out;
 	}
 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {