qcacld-3.0: Correct BW parameter for CSA concurrency check

In SAP+GO concurrency, if move SAP to DFS channel (BW 160 MHz)
and cause MCC with GO, the target will do CAC on SAP, but target
doesn't support MCC with GO when SAP is CAC state.
Fix by checking correct BW of CSA target channel so that correct
DFS flag can be got and if target channel is DFS causing MCC
with other AP interface then reject CSA request.

Change-Id: Ic7821cf62d3b364e4d2ea052dc82d65d18054091
CRs-Fixed: 3275285