Merge branch 's390-qeth-fixes'

Julian Wiedmann says:

====================
s390/qeth: fixes 2020-03-10

This fixes three minor issues:
1) a setup parameter gets cleared unnecessarily when the HW config
   changes,
2) insufficient error handling when initially filling the RX ring, and
3) a rarely used worker that needs to be cancelled during tear down.
====================

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