ext4: make ext4_delete_entry generic

Currently ext4_delete_entry() is used only for dir entry removing from
a dir block.  So let us create a new function
ext4_generic_delete_entry and this function takes a entry_buf and a
buf_size so that it can be used for inline data.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index a971b65..6cfe546 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2129,6 +2129,13 @@
 		      const struct qstr *d_name,
 		      unsigned int offset,
 		      struct ext4_dir_entry_2 **res_dir);
+extern int ext4_generic_delete_entry(handle_t *handle,
+				     struct inode *dir,
+				     struct ext4_dir_entry_2 *de_del,
+				     struct buffer_head *bh,
+				     void *entry_buf,
+				     int buf_size,
+				     int csum_size);
 
 /* resize.c */
 extern int ext4_group_add(struct super_block *sb,