ath9k_hw: inform ANI calibration when scanning

The new ANI implementation will use this to skip ANI
calibration upon a scan. This cannot be ported to the
older ANI implementation unless default ANI values from
the ANI are also used upon a scan. This is essentially
what one of the things thenew ANI does.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>