qcacmn: Enable RCSA with subchannel information

Calculate the bitmap of subchannels that are affected by
radar and store in dfs structure along with flags

Algorithm:
	1). Given the radar affected subchannels list, create a
	NOL bitmap, where
	1 - Radar hit on Subchannel.
	0 - Subchannel not affected.

	2). Along with the NOL bitmap, send the Minimum Bandwidth
	for each subchannel and the Channel list's starting
	channel's centre frequency.

	Example:
	Mode : 100HT80, if radar affected subchannels are 100, 104
	and 108.
	NOL bandwidth: 20.
	NOL start frequency: 5500.
	NOL Bitmap: 11100000.

	3). During precac (precac timer running), if radar hits
	at secondary segment, the umac code that sends rcsa
	is still called, but add a new flag to not send rcsa, and
	in rootAP, channel change is not triggered, only NOL
	is updated.

Add APIs that can be called from mlme to fetch the NOL and IE
flags information from DFS structure during RCSA framing.

If subchannel marking is disabled, the new NOL bitmap has no meaning
and is hence, not sent.

CRs-Fixed: 2328377
Change-Id: I3114ff5ca2704c316c9dc83220740fac9a6a00a1
4 files changed