selftests: netdevsim: sprinkle more udevadm settle

Number of tests are failing when netdev renaming is active
on the system. Add udevadm settle in logic determining
the names.

Fixes: 242aaf03dc9b ("selftests: add a test for ethtool pause stats")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240114224726.1210532-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

selftests: net: test ethtool -L vs mq

Add a selftest for checking mq children are visible after ethtool -L.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: ethtool: add a netdevsim FEC test

Test FEC settings, iterate over configs.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: refactor get_netdev_name function

As pointed out by Michal Kubecek, getting the name
with the previous approach was racy, it's better
and easier to get the name of the device with this
patch's approach.

Essentialy the function doesn't need to exist
anymore as it's a simple 'ls' command.

Signed-off-by: Antonio Cardace <acardace@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: extract common functions in ethtool-common.sh

Factor out some useful functions so that they can be reused
by other ethtool-netdevsim scripts.

Signed-off-by: Antonio Cardace <acardace@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>