Revert "netlink: test for all flags of the NLM_F_DUMP composite"

This reverts commit 0ab03c2b1478f2438d2c80204f7fef65b1bca9cf.

It breaks several things including the avahi daemon.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index f83cb37..1781d99 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -519,7 +519,7 @@
 	    security_netlink_recv(skb, CAP_NET_ADMIN))
 		return -EPERM;
 
-	if ((nlh->nlmsg_flags & NLM_F_DUMP) == NLM_F_DUMP) {
+	if (nlh->nlmsg_flags & NLM_F_DUMP) {
 		if (ops->dumpit == NULL)
 			return -EOPNOTSUPP;