parisc: fix dev_printk() compile warnings for accessing a device struct

Fix compile warnings:
drivers/scsi/zalon.c: In function `zalon_probe':
drivers/scsi/zalon.c:140: warning: passing arg 1 of `dev_driver_string' from incompatible pointer type
drivers/scsi/zalon.c:140: warning: passing arg 1 of `dev_name' from incompatible pointer type

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>