Merge patch series "fs: ext4: implement opendir, readdir, closedir"

Heinrich Schuchardt <heinrich.schuchardt@canonical.com> says:

With this series opendir, readdir, closedir are implemented for ext4.
These functions are needed for the UEFI sub-system to interact with
the ext4 file system.

To reduce code growth the functions are reused to implement the ls
command for ext4.

A memory leak in ext4fs_exists is resolved.

ext4fs_iterate_dir is simplified by removing a redundant pointer copy.

Link: https://lore.kernel.org/r/20241026064048.370062-1-heinrich.schuchardt@canonical.com