xdr: Add an export for the helper function write_bytes_to_xdr_buf()

Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

net/sunrpc/xdr.c

@@ -762,6 +762,7 @@ int write_bytes_to_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, un
 	__write_bytes_to_xdr_buf(&subbuf, obj, len);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(write_bytes_to_xdr_buf);
 
 int
 xdr_decode_word(struct xdr_buf *buf, unsigned int base, u32 *obj)