Merge branch 'qeth-fixes'

Julian Wiedmann says:

====================
s390/qeth: fixes 2018-09-12

please apply the following qeth fixes for -net.

Patch 1 resolves a regression in an error path, while patch 2 enables
the SG support by default that was newly introduced with 4.19.
Patch 3 takes care of a longstanding problem with large-order
allocations, and patch 4 fixes a potential out-of-bounds access.
====================

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