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
3 files changed