Wifi: Filter usable channels by Coex, Concurrency

Add ability to filter usable channel due to coex &
concurrency limitations. List of usable channels could
be limited due to coex restrictions and also due to
concurrency limitations & connection state.

Bug: 160212907
Test: VTS - VtsHalWifiV1_5TargetTest
Change-Id: Ic36b792b93fc4a6e328b9bc606a5286b8c1fd690