qcacld-3.0: Ignore CSA request for invalid channel

In present scenario, STA disconnects with AP if it receives
invalid channel in CSA IE. In this case STA shouldn't
disconnect with AP as this request may come from a spoof AP.

Ignore this CSA request as it might be from spoof AP and
if it is from genuine AP heart beat failure happens and
results in disconnection. After disconnection DUT may
reconnect to same or other APs.

Change-Id: I840508dd27d8c313a3e8f74c4e1f5aa64eecf6f9
CRs-Fixed: 3390251