kernel: bump to 4.4.46

Refreshed patches for all supported targets.

Compile-tested on ar71xx, cns3xxx, imx6, mt7621, oxnas and x86/64.
Run-tested on ar71xx, cns3xxx, imx6 and mt7621.

Tested-by: Stijn Segers <francesco.borromini@inventati.org>
Signed-off-by: Koen Vandeputte <koen.vandeputte@ncentric.com>