Staging: comedi: adl_pci9118: fractured spelling fixed

a fractured spelling in previous style issue fix mended.
Signed-off-by: Sam Asadi <asadi.samuel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/adl_pci9118.c

@@ -412,7 +412,7 @@ static int check_channel_list(struct comedi_device *dev,
 			if ((CR_AREF(chanlist[i]) == AREF_DIFF) !=
 			    (differencial)) {
 				comedi_error(dev,
-					     "Differencial and single ended inputs can't be mixtured!");
+					     "Differential and single ended inputs can't be mixtured!");
 				return 0;
 			}
 			if ((CR_RANGE(chanlist[i]) < PCI9118_BIPOLAR_RANGES) !=