Similar to 874bd545 ("pxar: fix anchored exclusion at archive root"),
but this time for inclusion. Because of the inconsistency, it could
happen that a file included in generate_directory_file_list() got
excluded in add_entry(), e.g. with a .pxarexclude file like
> *
> !/supposed-to-be-included
Reported-by: Dominik Csapak <d.csapak@proxmox.com>
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>