[SCSI] Return -EINVAL when "id == max_id" in scsi_scan_host_selected()

The scsi_scan_host_selected() should return -EINVAL when the id is equal
to the max_id. Currently it uses ">" when comparing with max_id, and
hence leaves the border case when "id==max_id".
The channel and lun have values valid from 0 up to,
and including, max_channel or max_lun. But, the valid values for id
range from 0 to max_id-1. This patch fixes the problem.

Signed-off-by: Amit Arora <aarora@in.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>