[SCSI] dpt_i2o: sysfs code

Create a /sys/class/dpt_i2o directory and populate it with
dptiN directories. Each dptiN directory contains a "dev" file
that makes udev create /dev/dptiN

Signed-off-by: Miquel van Smoorenburg <miquels@cistron.nl>
Acked-by: Mark Salyzyn <Mark_Salyzyn@adaptec.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>