wireless: Reset beacon_found while updating regulatory

During the association, the regulatory is updated by country IE
that reaps the previously found beacons. The impact is that
after a STA disconnects *or* when for any reason a regulatory
domain change happens the beacon hint flag is not cleared
therefore preventing future beacon hints to be learned.
This is important as a regulatory domain change or a restore
of regulatory settings would set back the passive scan and no-ibss
flags on the channel. This is the right place to do this given that
it covers any regulatory domain change.

Cc: [e-mail]
Reviewed-by: Luis R. Rodriguez <[e-mail]>
Signed-off-by: Rajkumar Manoharan <[e-mail]>
Acked-by: Luis R. Rodriguez <[e-mail]>
Signed-off-by: John W. Linville <[e-mail]>

net/wireless/reg.c

···
 		return;
 	}
 
+	chan->beacon_found = false;
 	chan->flags = flags | bw_flags | map_regdom_flags(reg_rule->flags);
 	chan->max_antenna_gain = min(chan->orig_mag,
 		(int) MBI_TO_DBI(power_rule->max_antenna_gain));