Merge branch 's390-qeth-fixes'

Julian Wiedmann says:

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s390/qeth: fixes 2018-02-27

please apply some more qeth patches for -net and stable.

One patch fixes a performance bug in the TSO path. Then there's several
more fixes for IP management on L3 devices - including a revert, so that
the subsequent fix cleanly applies to earlier kernels.
The final patch takes care of a race in the control IO code that causes
qeth to miss the cmd response, and subsequently trigger device recovery.
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Signed-off-by: David S. Miller <davem@davemloft.net>