staging: comedi: cb_das16_cs: probe for the device first

During the attach of the comedi_driver, the device type probe
can fail. We should do the probe before requesting the irq
for the driver.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: Frank Mori Hess <fmhess@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>