Make css_probe_device static and remove an unimplemented prototype.
Reviewed-by: NPeter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>