at91: move to 4.4 kernel

Signed-off-by: Ben Whitten <ben.whitten@gmail.com>

SVN-Revision: 48353

target/linux/at91/Makefile

@@ -1,4 +1,4 @@
-# 
+#
 # Copyright (C) 2006-2013 OpenWrt.org
 #
 # This is free software, licensed under the GNU General Public License v2.
@@ -13,7 +13,7 @@ BOARDNAME:=Atmel AT91
 FEATURES:=squashfs targz ext2 usb usbgadget ubifs
 SUBTARGETS:=legacy sama5d3
 
-KERNEL_PATCHVER:=3.18
+KERNEL_PATCHVER:=4.4
 
 include $(INCLUDE_DIR)/target.mk