Merge branch 's390-qeth-next'

Julian Wiedmann says:

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s390/qeth: updates 2019-02-12

please apply one more round of qeth patches to net-next.
This series targets the driver's control paths. It primarily brings improvements
to the error handling for sent cmds and received responses, along with the
usual cleanup and consolidation efforts.
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Signed-off-by: David S. Miller <davem@davemloft.net>