ext4: drop EXT4_EX_NOFREE_ON_ERR from rest of extents handling code

Drop EXT4_EX_NOFREE_ON_ERR from ext4_ext_create_new_leaf(),
ext4_split_extent(), ext4_convert_unwritten_extents_endio().

This requires fixing all of their callers to potentially
ext4_ext_find_extent() to free the struct ext4_ext_path object in case
of an error, and there are interlocking dependencies all the way up to
ext4_ext_map_blocks(), ext4_swap_extents(), and
ext4_ext_remove_space().

Once this is done, we can drop the EXT4_EX_NOFREE_ON_ERR flag since it
is no longer necessary.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/migrate.c

@@ -81,7 +81,7 @@ static int finish_range(handle_t *handle, struct inode *inode,
 				goto err_out;
 		}
 	}
-	retval = ext4_ext_insert_extent(handle, inode, path, &newext, 0);
+	retval = ext4_ext_insert_extent(handle, inode, &path, &newext, 0);
 err_out:
 	up_write((&EXT4_I(inode)->i_data_sem));
 	if (path) {