ath9k_hw: fix dual band assumption for XB113

ath9k_hw: fix dual band assumption for XB113

commit 9ba7f4f5eba5f4b44c7796bbad29f8ec3a7d5864 upstream.

The XB113 cards are single band, 5 GHz-only, but the
default settings were configured to assume it was dual
band. Users of these cards then would see 2.4 GHz channels
but you would never get any scan results from these channels
given that the radio is not present.

Cc: Fiona Cain <Fiona.Cain@atheros.com>
Cc: Ray Li <ray.li@greenwavereality.com>
Cc: Kathy Giori <kathy.giori@atheros.com>
Cc: Aeolus Yang <aeolus.yang@atheros.com>
Cc: Dan Friedman <dan.friedman@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>