[S390] dasd whitespace and other cosmetics.

Dasd code cleanup: 1) remove white space, 2) remove the emacs override
sections, and 3) use kzalloc instead of kmalloc.

Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>