[PATCH] s390: fix slab debugging

With CONFIG_SLAB_DEBUG=y networking over qeth doesn't work.  The problem is
that the qib structure embedded in the qeth_irq structure needs an alignment
of 256 but kmalloc only guarantees an alignment of 8.  When using SLAB
debugging the alignment of qeth_irq is not sufficient for the embedded qib
structure which causes all users of qdio (qeth and zfcp) to stop working.
Allocate qeth_irq structure with __get_free_page.  That wastes a small amount
of memory (~2500 bytes) per online adapter.

Signed-off-by: Christian Borntraeger <cborntra@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>