qcacld-3.0: Free channel-list memory from Sap_context

The driver allocates memory to channelist in the API
sap_get_channel_list, and stores the pointer to channel
list in sap_context, and frees the memory allocated for
the same in scan request callback.
But it may happen that before the callback, stop adapter
calls wlansap_context_put and frees the memory allocated
to sap context, without the mem free of channellist, which
results in a mem leak

Fix is to add a NULL check to sap context and free the memory
allocated to the sap context channel list in
sap_cleanup_channel_list.

Change-Id: I7030ca8325ae4c968db654bf14062e332f409b87
CRs-Fixed: 2254767
1 file changed