staging: comedi: cb_pcimdas: cleanup "find pci device" code

Add a couple local variables to make the tests more concise.

Reorder the tests to make the for() loop checking for a
matching boardtype quicker.

Use ARRAY_SIZE() to determine the number of boards instead
of the hard-coded '1'.

Drop the dev_dbg for a match. It's just add noise.

Reword the dev_err when no match is found.

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