[package] add a workaround for devices that only start beaconing after scanning, that is almost every driver except b43

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@15041 3c298f89-4303-0410-b956-a3cf2f4a3e73

package/mac80211/files/lib/wifi/mac80211.sh

@@ -174,6 +174,7 @@ enable_mac80211() {
 				# special case where physical interface should be down for mesh to work
 				ifconfig "$ifname" down
 				ifconfig "msh$mesh_idx" up
+				iwlist msh$mesh_idx scan 2>/dev/null >/dev/null
 			;;
 		esac
 		first=0