[PATCH] md/raid1: fix build breakage

[Alexander Beregalov <a.beregalov@gmail.com>]

Fix this build error:
drivers/md/raid1.c: In function 'raid1_congested':
drivers/md/raid1.c:589: error: 'BDI_write_congested' undeclared

BDI_write_congested was changed in 1faa16d2
(block: change the request allocation/congestion logic to be sync/async
based)

Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
---

 drivers/md/raid1.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index f2247b0..274b491 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -586,7 +586,7 @@ static int raid1_congested(void *data, int bits)
 			/* Note the '|| 1' - when read_balance prefers
 			 * non-congested targets, it can be removed
 			 */
-			if ((bits & (1<<BDI_write_congested)) || 1)
+			if ((bits & (1<<BDI_async_congested)) || 1)
 				ret |= bdi_congested(&q->backing_dev_info, bits);
 			else
 				ret &= bdi_congested(&q->backing_dev_info, bits);