Merge branch 'net-generic-selftest-support'

Oleksij Rempel says:

====================
provide generic net selftest support

changes v3:
- make more granular tests
- enable loopback for all PHYs by default
- fix allmodconfig build errors
- poll for link status update after switching to the loopback mode

changes v2:
- make generic selftests available for all networking devices.
- make use of net_selftest* on FEC, ag71xx and all DSA switches.
- add loopback support on more PHYs.

This patch set provides diagnostic capabilities for some iMX, ag71xx or
any DSA based devices. For proper functionality, PHY loopback support is
needed.
So far there is only initial infrastructure with basic tests.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>