ext4: add missing kfree() on error return path in add_new_gdb()

We added some more error handling in b4097142 "ext4: add error
checking to calls to ext4_handle_dirty_metadata()".  But we need to
call kfree() as well to avoid a memory leak.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

fs/ext4/resize.c

@@ -517,6 +517,7 @@ static int add_new_gdb(handle_t *handle, struct inode *inode,
 	return err;
 
 exit_inode:
+	kfree(n_group_desc);
 	/* ext4_handle_release_buffer(handle, iloc.bh); */
 	brelse(iloc.bh);
 exit_dindj: