staging: pi433: Split subtraction across 2 lines

Split a subtraction across 2 lines in order to make these lines
no longer than 80 columns. Problem found with checkpatch.

Signed-off-by: Eisha Chen-yen-su <[e-mail]>
Acked-by: Julia Lawall <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/staging/pi433/pi433_if.c

···
 
 		/* need to drop bytes or acquire? */
 		if (dev->rx_bytes_to_drop > dev->rx_bytes_dropped)
-			bytes_to_read = dev->rx_bytes_to_drop - dev->rx_bytes_dropped;
+			bytes_to_read = dev->rx_bytes_to_drop -
+					dev->rx_bytes_dropped;
 		else
 			bytes_to_read = bytes_total - dev->rx_position;