f2fs: remove repeated F2FS_SET_SB_DIRT call

F2FS_SET_SB_DIRT is called in inc_page_count and
it is directly called one more time in the next line.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index d3b34d0..2887c19 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -164,7 +164,6 @@
 	if (!PageDirty(page)) {
 		__set_page_dirty_nobuffers(page);
 		inc_page_count(sbi, F2FS_DIRTY_META);
-		F2FS_SET_SB_DIRT(sbi);
 		return 1;
 	}
 	return 0;