Enable 6-bit path control for give better compare between parent's.

Change-Id: Ia1e265fd0bcfa8e128bcb9dc34e22fd91c353bb4

Author: Juha Heiskanen

source/6LoWPAN/ws/ws_bbr_api.c

@@ -55,7 +55,7 @@ static void ws_bbr_rpl_root_activate(uint8_t *dodag_prefix, uint8_t *dodag_id)
         .lifetime_unit = 60,
         .objective_code_point = 1, // MRHOF algorithm used
         .authentication = 0,
-        .path_control_size = 1,
+        .path_control_size = 5,
         .dag_max_rank_increase = 2048,
         .min_hop_rank_increase = 128,
         // DIO configuration