cfg80211: respect API on orig_flags on channel for beacon hint

As part of our documented API we always respect the orig_flag
settings on a channel. We forgot to follow this for the beacon
hints.

Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>