block/fs/drivers: remove rw argument from submit_bio

This has callers of submit_bio/submit_bio_wait set the bio->bi_rw
instead of passing it in. This makes that use the same as
generic_make_request and how we set the other bio fields.

Signed-off-by: Mike Christie <mchristi@redhat.com>

Fixed up fs/ext4/crypto.c

Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/block/blk-flush.c b/block/blk-flush.c
index b1c91d2..3af4a5a 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -485,8 +485,9 @@
 
 	bio = bio_alloc(gfp_mask, 0);
 	bio->bi_bdev = bdev;
+	bio->bi_rw = WRITE_FLUSH;
 
-	ret = submit_bio_wait(WRITE_FLUSH, bio);
+	ret = submit_bio_wait(bio);
 
 	/*
 	 * The driver must store the error location in ->bi_sector, if