mwan3: use default routes from additional tables

Until now the additional tables listed in gobal 'rt_table_lookup' were
not considered for interfaces.
In order to be able to also use interface-defined routes from tables
other than main, consider also tables listed in 'rt_table_lookup'.
Update version to 2.10.10 as requested by maintainer.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>