f2fs: send REQ_META or REQ_PRIO when reading meta area

Let's send REQ_META or REQ_PRIO when reading meta area such as NAT/SIT
etc.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 33ab378..1e837139 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -1734,13 +1734,13 @@
 			continue;
 		}
 
-		submit_read_page(sbi, page, blk_addr, READ_SYNC);
+		submit_read_page(sbi, page, blk_addr, READ_SYNC | REQ_META);
 
 		mark_page_accessed(page);
 		f2fs_put_page(page, 0);
 	}
 
-	f2fs_submit_read_bio(sbi, READ_SYNC);
+	f2fs_submit_read_bio(sbi, READ_SYNC | REQ_META);
 	return blkno - start;
 }