cfg80211: Do not compare with boolean in nl80211_common_reg_change_event

With the help of boolinit.cocci, we use !nl80211_reg_change_event_fill
instead of (nl80211_reg_change_event_fill == false). Meanwhile, Clean
up the code.

Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Link: https://lore.kernel.org/r/1567657537-65472-1-git-send-email-zhongjiang@huawei.com


Signed-off-by: Johannes Berg <johannes.berg@intel.com>