ath: fix 0x6C for beaconing/passive scan flags based on country IE

The 0x6C regulatory domain is just like the 0x6A regulatory
domain but differs in that 0x6C will allow adhoc and active
scan on its channels only if we are associated to an AP
with a country IE that allows those channels. The
ath_reg_apply_beaconing_flags() does just this -- we respect
the manufacturer's intent on only enabling beaconing modes
of operation if and only if blessed by the country IE.

Cc: David Quan <david.quan@atheros.com>
Cc: Senthil Balasubramanian <senthilkumar@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>