wireless: rt2x00: add new rt2800usb device

0x1b75 0xa200 AirLive WN-200USB wireless 11b/g/n dongle

References: https://bugs.debian.org/766802


Reported-by: Martin Mokrejs <mmokrejs@fold.natur.cuni.cz>
Cc: stable@vger.kernel.org
Signed-off-by: Cyril Brulebois <kibi@debian.org>
Acked-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>