SUNRPC: xdr_get_next_encode_buffer should be declared static

Quell another sparse warning.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

net/sunrpc/xdr.c

@@ -509,7 +509,8 @@ void xdr_commit_encode(struct xdr_stream *xdr)
 }
 EXPORT_SYMBOL_GPL(xdr_commit_encode);
 
-__be32 *xdr_get_next_encode_buffer(struct xdr_stream *xdr, size_t nbytes)
+static __be32 *xdr_get_next_encode_buffer(struct xdr_stream *xdr,
+		size_t nbytes)
 {
 	static __be32 *p;
 	int space_left;