config: CONFIG_RT2800USB_RT55XX for more RaLink ID

I added CONFIG_RT2800USB_RT55XX=y to have my el cheapo dual band wlan adapter (RaLink chip, MediaTek brand, 148f:5572) supported by RT2800. I tested with 3.10.27+ and it works. 5GHz for 5-10 Euro.
Merge pull request #515 from juleq/patch-1

config: CONFIG_RT2800USB_RT55XX for more RaLink ID