drbd: Allow larger values for c-fill-target.

Connections through a compressing proxy might have more bits
on the fly. 500MByte instead of 50MByte

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index ff7fffa..1680939 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -348,7 +348,7 @@
 struct p_header95 {
 	u16	  magic;	/* use DRBD_MAGIC_BIG here */
 	u16	  command;
-	u32	  length;
+	u32	  length;	/* Use only 24 bits of that. Ignore the highest 8 bit. */
 	u8	  payload[0];
 } __packed;