This adds an easy-installation factory image for the NETGEAR R6220
router. The factory image can either be flashed via the vendor Web-UI or
the bootloader using nmrpflash.
Tested with NETGEAR V1.1.0.86 firmware.
Signed-off-by: David Bauer <mail@david-bauer.net>
(cherry picked from commit 607dfdf211)