qcacld-3.0: Clear sap ctx channel list in undo acs

Currently the sap ctx's channel list is not freed
as part of undo acs, and hence can lead to mem leak
when the do acs and SSR is triggered in parallel.
Scenario:-
1. Turn on SAP
2. Do SSR in parallel
3. Unload WLAN

Fix is to clear the channel list as part of undo
acs.

Change-Id: Ie8dcace1d32aeec2621e785d793290d70c194f62
CRs-Fixed: 2511752

core/sap/inc/sap_api.h

@@ -1322,6 +1322,17 @@ QDF_STATUS wlansap_acs_chselect(struct sap_context *sap_context,
 				struct sap_config *config,
 				void *pusr_context);
 
+/**
+ * sap_undo_acs() - Undo acs i.e free the allocated ch lists
+ * @sap_ctx: pointer to the SAP context
+ *
+ * This function will free the memory allocated to the sap ctx channel list, acs
+ * cfg ch list and master ch list.
+ *
+ * Return: None
+ */
+void sap_undo_acs(struct sap_context *sap_context);
+
 /**
  * wlansap_get_chan_width() - get sap channel width.
  * @sap_ctx: pointer to the SAP context