Hotpluggable interfaces are already brought up before /etc/init.d/network boot
and this change can break them, if the ifup -a command runs at the wrong time,
also starts many interfaces twice, which can lead to issues with PPPoE.
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@17516 3c298f89-4303-0410-b956-a3cf2f4a3e73