Add vendor ID for AMBIT and use it to set the ath5k LED gpio.

base.c:
Changes-licensed-under: 3-Clause-BSD
Signed-off-by: NTulio Magno Quites Machado Filho <tuliom@gmail.com>
Acked-by: NBob Copeland <me@bobcopeland.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>