s390x/ioinst: Add missing alignment checks for IO instructions

The IO instructions MSCH, SSCH, STSCH, TSCH, STCRW and TPI require
that the second operand address must be aligned on a word boundary.

Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
