[GENL]: Add genlmsg_reply() to simply unicast replies to requests

A generic netlink user has no interest in knowing how to
address the source of the original request.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/genetlink.h b/include/net/genetlink.h
index 2010465..797c18b 100644
--- a/include/net/genetlink.h
+++ b/include/net/genetlink.h
@@ -150,6 +150,16 @@
 }
 
 /**
+ * genlmsg_reply - reply to a request
+ * @skb: netlink message to be sent back
+ * @info: receiver information
+ */
+static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
+{
+	return genlmsg_unicast(skb, info->snd_pid);
+}
+
+/**
  * gennlmsg_data - head of message payload
  * @gnlh: genetlink messsage header
  */