f2fs: trigger release_dirty_inode in f2fs_put_super

The generic_shutdown_super calls sync_filesystem, evict_inode, and then
f2fs_put_super. In f2fs_evict_inode, we remain some dirty inode information
so we should release them at f2fs_put_super.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 7e1c13b..f14af91 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -348,7 +348,7 @@
 	return e ? true : false;
 }
 
-static void release_dirty_inode(struct f2fs_sb_info *sbi)
+void release_dirty_inode(struct f2fs_sb_info *sbi)
 {
 	struct ino_entry *e, *tmp;
 	int i;