Changed example bssid in site.conf to a valid one (in terms of config file parsing)

docs/site-example/site.conf

@@ -45,9 +45,9 @@
     -- HT40+ (2x 20MHz channels, secondary above)
     htmode = 'HT20',
 
-    -- Adjust these values! ff... will not work!
-    mesh_ssid = 'ff:ff:ff:ff:ff:ff',  -- ESSID used for mesh
-    mesh_bssid = 'ff:ff:ff:ff:ff:ff', -- BSSID used for mesh
+    -- Adjust these values!
+    mesh_ssid = 'XX:XX:XX:XX:XX:XX',  -- ESSID used for mesh
+    mesh_bssid = 'XX:XX:XX:XX:XX:XX', -- BSSID used for mesh
 
     -- Bitrate used for multicast/broadcast packets.
     mesh_mcast_rate = 12000,
@@ -60,8 +60,8 @@
     ssid = 'luebeck.freifunk.net',
     channel = 44,
     htmode = 'HT20',
-    mesh_ssid = 'ff:ff:ff:ff:ff:ff',
-    mesh_bssid = 'ff:ff:ff:ff:ff:ff',
+    mesh_ssid = 'XX:XX:XX:XX:XX:XX',
+    mesh_bssid = 'XX:XX:XX:XX:XX:XX',
     mesh_mcast_rate = 12000,
   },