kernel: update to v4.4.23

Refresh patches for all targets that support kernel 4.4.
compile/run-tested on brcm2708/bcm2710 only.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

target/linux/generic/patches-4.4/645-bridge_multicast_to_unicast.patch

@@ -169,7 +169,7 @@ Implement optinal multicast->unicast conversion for igmp snooping
  			err = br_ip6_multicast_add_group(br, port,
 -							 &grec->grec_mca, vid);
 +							 &grec->grec_mca, vid, src);
- 			if (!err)
+ 			if (err)
  				break;
  		}
 @@ -1427,7 +1453,8 @@ br_multicast_leave_group(struct net_brid