Staging: comedi: fix prink warning style issue in ni_daq_700.c

This is a patch to the ni_daq_700.c file that fixes up a prink  warning found by the checkpatch.pl tool

Signed-off-by: Ravishankar <ravishankarkm32@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>