bugfix: Radio0Path is unknonw WIFI doesn't start.

wifi detect  is called in /etc/init.d/boot before uci_apply_defaults is called.

Because of this if we don't have the data about the radio0path we need to remove the wifi config file first before calling wifi detect.

files/etc/uci-defaults/99_setup_aredn_include

@@ -60,6 +60,7 @@ fi
 if [ -z "$(uci -q get wireless.radio0.path)" ]
 then
   mkdir -p /etc/aredn_include
+  rm -f /etc/config/wireless
   wifi detect|grep "option path"|head -n 1 > /etc/aredn_include/radio0path
   wifi detect > /etc/config/wireless
 else