Following are a part of this change:-
1. Add an API to check if PreCAC/RCAC is enabled. This API is used before
delivering an external event to Agile SM.
2. Post an event to the Agile PreCAC SM if Radar is found on
agile channel. Radar on primary channel is taken care of by the
ensuing channel change.
3. Move all Agile PreCAC changes under macro QCA_SUPPORT_AGILE_DFS,
only RCAC specific changes remain under QCA_SUPPORT_ADFS_RCAC.
Change-Id: I45d4b9f826d36e9e4093879b394165a15a52f324