add local_mode config option

This prevents communication with other usteer nodes and allows it to be
used for purely local band steering / load balancing

Signed-off-by: Felix Fietkau <nbd@nbd.name>

usteer.h

@@ -149,6 +149,7 @@ struct usteer_config {
 	uint32_t debug_level;
 
 	bool ipv6;
+	bool local_mode;
 
 	uint32_t sta_block_timeout;
 	uint32_t local_sta_timeout;