if_tunnel: Update IFLA defines up to FWMARK
if_tunnel: Update IFLA defines up to FWMARK

This is a new option that was added in Linux v4.12.

Signed-off-by: Thomas Winter <c288344b3d74b2272273a50be2749654d1dcbb64@alliedtelesis.co.nz>

greearb/libnl-ct,thom311/libnl,greearb/libnl-ct,thom311/libnl,thom311/libnl,greearb/libnl-ct