This converts argument identification from 'target0' to real name of
target.

This changes check from carrier being up to just interface being up.
That is actually the correct check we want to do. The carrier might be
down if we are connected directly to board (not trough switch) and thus
this test might fail even if everything is all right. In reality we want
to check that interface is set to be up and thus is going to be up once
carrier is up. This information is encoded in flags as lowest bit (this
was discovered by checking flag value rather not from documentation). So
this test now only checks if this bit is set or not.

Karel Koci authored Mar 18, 2021 and Karel Koci committed Apr 13, 2021

This removes concept of exclusive device. The only use of it was to pass
exclusive access to network interface but that is not essentially
required as it is even more versatile to use macvlan as thus we can
easily spawn multiple containers to simulate network.
The only known use for physical device pass trough and thus exclusive is
Wi-Fi. It won't be possible to use macvlan for it. At the same time this
is not an issue as it is not expected that we are going to be reusing
this interface in single tests run multiple times over and over. In the
end there is no need to automatically suspend containers to steal
devices as it has been implemented (and in reality not finished).

The introduced device management now required all devices to be defined
in image as attributes. This gives image definition control over name of
this device in container. It is up to container user to assign
appropriate real device for it. This is done using device map that is
simply pair of attribute and real device specifier. This concept can be
in future expanded to even encode additional configuration if have need
for it.