s390x/css: handle format-0 TIC CCW correctly

For TIC CCW, bit positions 8-32 of the format-1 CCW must contain zeros;
otherwise, a program-check condition is generated. For format-0 TIC CCWs,
bits 32-63 are ignored.

To convert TIC from format-0 CCW to format-1 CCW correctly, let's clear
bits 8-32 to guarantee compatibility.

Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
