f2fs: remove the rw_flag domain from f2fs_io_info

When using the f2fs_io_info in the low level, we still need to merge the
rw and rw_flag, so use the rw to hold all the io flags directly,
and remove the rw_flag field.

ps.It is based on the previous patch:
f2fs: move all the bio initialization into __bio_alloc

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 3565caf..0af0a71 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -94,8 +94,7 @@
 	int i;
 	struct f2fs_io_info fio = {
 		.type = META,
-		.rw = READ_SYNC,
-		.rw_flag = REQ_META | REQ_PRIO
+		.rw = READ_SYNC | REQ_META | REQ_PRIO
 	};
 
 
@@ -1581,8 +1580,7 @@
 	int page_idx = start;
 	struct f2fs_io_info fio = {
 		.type = META,
-		.rw = READ_SYNC,
-		.rw_flag = REQ_META | REQ_PRIO
+		.rw = READ_SYNC | REQ_META | REQ_PRIO
 	};
 
 	for (; page_idx < start + nrpages; page_idx++) {