mmc: card: Fix packing control enabling algorithm

When hitting a stop potential packing event, we should zero
num_of_potential_packed_wr_reqs, so that the packing won't be
enabled too early.

Change-Id: I91d36765c4a50be0e2805cd07c58962fb87153c6
Signed-off-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Tatyana Brokhman <tlinder@codeaurora.org>
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index 383992d8..8c76ace 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -1980,6 +1980,7 @@
 		if (mq->num_of_potential_packed_wr_reqs >
 				mq->num_wr_reqs_to_start_packing)
 			mq->wr_packing_enabled = true;
+		mq->num_of_potential_packed_wr_reqs = 0;
 		return;
 	}