f2fs: enable inline dir handling

Add inline dir functions into normal dir ops' function to handle inline ops.
Besides, we enable inline dir mode when a new dir inode is created if
inline_data option is on.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 80d9a04..d054e0e 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -314,7 +314,7 @@
 		goto fail;
 
 	/* handle inline data case */
-	if (f2fs_has_inline_data(inode)) {
+	if (f2fs_has_inline_data(inode) || f2fs_has_inline_dentry(inode)) {
 		if (whence == SEEK_HOLE)
 			data_ofs = isize;
 		goto found;