Extendprefix is typically used to extend an IPv6 RA prefix from a mobile
wan link to the LAN; such scenario requires correct RA prefix settings
like the on link flag not being set.
However some mobile manufacter set the RA prefix on link flag which breaks
basic IPv6 routing.
Work around this issue by filtering out the route being equal to the
extended prefix.
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>
Hans Dedecker