qcacld-3.0: Abort cds_deinit_policy_mgr if context is null

Avoid null pointer de-reference.

Change-Id: I5f07ab5eba0d24512a06c5426427ad67ee6f798d
CRs-Fixed: 1081073

core/cds/src/cds_concurrency.c

@@ -3963,8 +3963,7 @@ QDF_STATUS cds_deinit_policy_mgr(void)
 	cds_ctx = cds_get_context(QDF_MODULE_ID_QDF);
 	if (!cds_ctx) {
 		cds_err("Invalid CDS Context");
-		status = QDF_STATUS_E_FAILURE;
-		QDF_ASSERT(0);
+		return QDF_STATUS_E_FAILURE;
 	}
 
 	if (!QDF_IS_STATUS_SUCCESS(qdf_event_destroy