proc_print_scsidevice is used for the scsi device listing in
/proc/scsi/scsi, but in addition two drivers (advansys and eata_pio)
are using it to duplicate the same information in their proc_info
method.  Remove that output and make the function static to
scsi_proc.c.  Also remove proc_scsi from the public headers - it
should really be private to the scsi midlayer but I don't think
we can shange the sg procfs name anymore.