brcm63xx: switch to linux 4.4

Boot tested on AR-5381u, AR-5387un and WAP-5813n

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

target/linux/brcm63xx/Makefile

@@ -1,5 +1,6 @@
 #
 # Copyright (C) 2006-2009 OpenWrt.org
+# Copyright (C) 2016 LEDE project
 #
 # This is free software, licensed under the GNU General Public License v2.
 # See /LICENSE for more information.
@@ -11,7 +12,7 @@ BOARD:=brcm63xx
 BOARDNAME:=Broadcom BCM63xx
 SUBTARGETS:=generic smp
 FEATURES:=squashfs usb atm pci pcmcia usbgadget
-KERNEL_PATCHVER:=4.1
+KERNEL_PATCHVER:=4.4
 MAINTAINER:=Jonas Gorski <jogo@openwrt.org>
 
 include $(INCLUDE_DIR)/target.mk