Staging: Comedi adv_pci1710: Fixed indentation

Fixed indentation for print messages and code.

Signed-off-by: Tomas Melin <tomas.melin@iki.fi>
Acked-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>