staging: comedi: adv_pci_dio: remove function trace messages

Remove the DPRINTK function trace messages and associated
PCI_DIO_EXTDEBUG define. These should not be in the final driver.

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>