Specify wiphy index while fetching driver country code

NL80211_CMD_GET_REG gives global country code information which may be
different from actual driver country code. Thus, use wiphy index while
fetching driver country code.

Also, the country code changes not subscribed with NetlinkUtils() when
there are no active interfaces in wificond internal structures. So,
fetch the current country code just before subscribing for country code
change events with NetlinkUtils() and broadcast to all registered
framework callbacks.

Bug: 314689364
Test: Manual - SoftAp turn on/off & verified the country code from
bugreport
Test: Manual - Wi-Fi turned ON and verified the country code from logs

Change-Id: I9a4e847abf1c5faa756ed3a624c350812e98bb8c
4 files changed