qcacld-3.0: Fix possible memory leak of hdd_medium_assess_timer

If hostapd stop bss happen together with SSR, it is possible
eSAP_STOP_BSS_EVENT not post and hdd_medium_assess_deinit()
miss to invoke.

Fix it by invoke hdd_medium_assess_deinit() in failure path.

Change-Id: I79814be745fab366e1073438a295414f7de3f69a
CRs-Fixed: 3037020

core/hdd/src/wlan_hdd_hostapd.c

@@ -6204,6 +6204,7 @@ static int __wlan_hdd_cfg80211_stop_ap(struct wiphy *wiphy,
 				hdd_place_marker(adapter, "STOP with FAILURE",
 						 NULL);
 				hdd_sap_indicate_disconnect_for_sta(adapter);
+				hdd_medium_assess_deinit();
 				QDF_ASSERT(0);
 			}
 		}