dnsmasq: Fix wrong format for --dhcp-boot option

dnsmasq --dhcp-boot option uses 'tag' instead of 'net' to specify tags

Signed-off-by: Julius Lehmann <[email protected]>

package/network/services/dnsmasq/files/dnsmasq.init

@@ -502,7 +502,7 @@ dhcp_boot_add() {
 
 	[ -n "$serveraddress" ] && [ ! -n "$servername" ] && return 0
 
-	xappend "--dhcp-boot=${networkid:+net:$networkid,}${filename}${servername:+,$servername}${serveraddress:+,$serveraddress}"
+	xappend "--dhcp-boot=${networkid:+tag:$networkid,}${filename}${servername:+,$servername}${serveraddress:+,$serveraddress}"
 
 	config_get_bool force "$cfg" force 0