device create: s390: convert device_create_drvdata to device_create

Now that device_create() has been audited, rename things back to the
original call to be sane.

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>