[AF_KEY]: no message type set

When returning a message to userspace in reply to a SADB_FLUSH or 
SADB_X_SPDFLUSH message, the type was not set for the returned PFKEY 
message. The patch below corrects this problem.
Signed-off-by: NJerome Borsboom <j.borsboom@erasmusmc.nl>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/key/af_key.c

@@ -1620,6 +1620,7 @@ static int key_notify_sa_flush(struct km_event *c)
 		return -ENOBUFS;
 	hdr = (struct sadb_msg *) skb_put(skb, sizeof(struct sadb_msg));
 	hdr->sadb_msg_satype = pfkey_proto2satype(c->data.proto);
+	hdr->sadb_msg_type = SADB_FLUSH;
 	hdr->sadb_msg_seq = c->seq;
 	hdr->sadb_msg_pid = c->pid;
 	hdr->sadb_msg_version = PF_KEY_V2;
@@ -2385,6 +2386,7 @@ static int key_notify_policy_flush(struct km_event *c)
 	if (!skb_out)
 		return -ENOBUFS;
 	hdr = (struct sadb_msg *) skb_put(skb_out, sizeof(struct sadb_msg));
+	hdr->sadb_msg_type = SADB_X_SPDFLUSH;
 	hdr->sadb_msg_seq = c->seq;
 	hdr->sadb_msg_pid = c->pid;
 	hdr->sadb_msg_version = PF_KEY_V2;