staging: comedi: rtd520: Resolve multiline dereference

Reformat multi-line dereferencing of function arguments
&cmd->scan_begin_arg. Problem detected by checkpatch script.
Signed-off-by: Deepak R Varma <mh12gx2825@gmail.com>
Link: https://lore.kernel.org/r/20200314214154.GA3904@deeUbuntuSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/rtd520.c

@@ -815,9 +815,8 @@ static int rtd_ai_cmdtest(struct comedi_device *dev,
 
 		if (cmd->scan_begin_src == TRIG_TIMER) {
 			arg = cmd->convert_arg * cmd->scan_end_arg;
-			err |= comedi_check_trigger_arg_min(&cmd->
-							    scan_begin_arg,
-							    arg);
+			err |= comedi_check_trigger_arg_min(
+					&cmd->scan_begin_arg, arg);
 		}
 	}