[SCSI] scsi_dh: Use scsi_devinfo functions to do matching of device_handler tables.

Previously we were using strncmp in order to avoid having to include
whitespace in the devlist, but this means "HSV1000" matches a device
list entry that says "HSV100", which is wrong.  This patch changes
scsi_dh.c to use scsi_devinfo's matching functions instead, since they
handle these cases correctly.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>