Staging: comedi: fix line over 80 character issue in cb_pcidda.c

This is a patch to the cb_pcidda.c file that fixes up a line over 80
character warning found by the checkpatch.pl tool

Signed-off-by: Ravishankar Karkala Mallikarjunayya <ravishankar.km@greenturtles.in>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>