genetlink: Introduce genl_register_family_with_ops()

This introduces genl_register_family_with_ops() that registers a genetlink
family along with operations from a table. This is used to kill copy'n'paste
occurrences in following patches.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/genetlink.h b/include/net/genetlink.h
index 747c255..1b0e3ee 100644
--- a/include/net/genetlink.h
+++ b/include/net/genetlink.h
@@ -88,6 +88,8 @@
 };
 
 extern int genl_register_family(struct genl_family *family);
+extern int genl_register_family_with_ops(struct genl_family *family,
+	struct genl_ops *ops, size_t n_ops);
 extern int genl_unregister_family(struct genl_family *family);
 extern int genl_register_ops(struct genl_family *, struct genl_ops *ops);
 extern int genl_unregister_ops(struct genl_family *, struct genl_ops *ops);