ramips: rt305x: add kernel support for AirLive AIR3GII

ramips: rt305x: add kernel support for AirLive AIR3GII

AirLive AIR3GII is Ralink RT5350F based device with
100Mbps switch, USB port, 4MB flash and 32MB ram.

Works: ethernet (LAN & WAN), wps button, led, USB, sysupgrade
Does not work: wifi (chip RT5350), reset button

[   13.390000] phy0 -> rt2800_init_eeprom: Error - Invalid RT chipset 0x5350 detected.
[   13.400000] phy0 -> rt2x00lib_probe_dev: Error - Failed to allocate device.

Other problem: LAN leds is reverse (lights when not cable
connected and vice versa)

[juhosg: move user-space support and image generation changes into
separate patches]

Signed-off-by: Cezary Jackiewicz <cezary.jackiewicz@gmail.com>
Patchwork: http://patchwork.openwrt.org/patch/2913/
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@34922 3c298f89-4303-0410-b956-a3cf2f4a3e73