staging: comedi: adl_pci9118: remove unnecessary dev->board_name initialization

The (*auto_attach) in this driver will set the dev->board_name and the comedi core
will set it when using the legacy (*attach). Remove the unnecessary initialization
in pci9118_common_attach().

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>