Show Wifi 'Off' status properly just after boot

If Wifi is not enabled at boot, WIFI_STATE_CHANGED_ACTION
sticky intent is not present. This results in Wifi 'Off'
status is not shown. This patch handles such case by calling
notifyChangeIfNeeded at register to refresh status.

Bug: 110373099
Test: manual - Check status after device boot with wifi off
Change-Id: I009386b03ef3269b00ce403b86087664b295f397