pm8001: fix printk typo in pm8001_hwi.c

Correct typo "unresgister" to "unregister" and "deviece" to
"device" in drivers/scsi/pm8001/pm8001_hwi.c

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>