cfg80211: move check for ignore_reg_update() on wiphy_update_regulatory()

This ensures that the initial REGDOM_SET_BY_CORE upon wiphy registration
respects the wiphy->custom_regulatory setting. Without this and if OLD_REG
is disabled (which will be default soon as we remove it) the
wiphy->custom_regulatory is simply ignored.

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