x86: remove old soekris config hacks, install a more appropriate default /etc/config/network with lan+wan

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@42888 3c298f89-4303-0410-b956-a3cf2f4a3e73