qcacld-3.0: Disable obss scan before suspend
When obss scan is enabled, FW will trigger scan periodically by
a timer. If a scan was triggered, FW need to access host memory
for data transfer. Occasionally, suspend may happen during one
scan, then FW is unable to access host memory and fw will crash.
So disable the obss scan before suspend.
Change-Id: I131258b3c975cc7fcf3931f4b1fc1e1a649383ef
CRs-Fixed: 2904237