qos-scripts: disable overhead calculation by default, it does not work properly for many line speeds

SVN-Revision: 25685

package/qos-scripts/files/etc/config/qos

@@ -4,7 +4,6 @@
 config interface wan
 	option classgroup  "Default"
 	option enabled      1
-	option overhead     1
 	option upload       128
 	option download     1024