Wifi: Chip level API to set the country code

Country code is global setting across the Wifi chip
and not really Wifi interface (STA or AP) specific.
Framework should have the ability to set the country
code on a chip level without requiring supplicant
instance to be running. As long as there is at least
one active interface to communicate to kernel driver,
country code can be set and driver should apply the
setting globally.

Bug: 149936939
Test: VTS - VtsHalWifiV1_5TargetTest
Change-Id: I1be5dae34b216a6152d09605d055872d5345507c