fix up the netconfig script after the devfs=>hotplug2 migration

SVN-Revision: 6542

target/linux/brcm-2.4/base-files/default/etc/init.d/netconfig

@@ -13,7 +13,7 @@ start() {
 			# WGT634u
 			echo boardtype=wgt634u
 		else
-			strings /dev/mtdblock/3
+			strings "$(find_mtd_part nvram)"
 		fi
 	) | awk '
 	function p(cfgname, name) {