The assumption that every MCU has this feature turned out wrong. Hence,
add a feature to allow testing for support of edge triggered IRQs on
both flanks.
The `ethernet` feature has not yet been used, so renaming it should not
cause any issue.
The goal is to eventually have a number of `netif_<type>` features that
would allow filtering boards by the time of connectivity the have.
This gets rid of a long list of boards with network interfaces and
instead let's boards (or MCUs with peripheral network interfaces)
provide the netif feature.
The apps that before used the long list are not depending on the
feature instead (in case of the default example, this is an
optional dependency).
Co-authored-by: mguetschow <mikolai.guetschow@tu-dresden.de>
Co-authored-by: mewen.berthelot <mewen.berthelot@orange.com>
