cfg80211: avoid restoring the regulatory during disconnect

Driver configures the default country code during bootup.
When STA disconnects, cfg80211 restore the regulatory setting
to world domain.cfg80211 should remain in the default country
code and not restore to world reg domain.

Change-Id: I01ccdc4d2831cf252a4b35f9f856f3256d9b7429
CRs-Fixed: 1023778
Signed-off-by: Sachin Ahuja <sahuja@codeaurora.org>
[joshc: fixed hunk in disconnect_work() - moved
cfg80211_is_all_countryie_ignore() check into new location, collapsed
conditional and use upstream REGULATORY_COUNTRY_IE_IGNORE regulatory
flag]
Signed-off-by: Josh Cartwright <joshc@codeaurora.org>