This reverts commit 1cdcc207.

This reverts commit 3848da13.

remove free space check as rsync_tmbackup will automatically purge old backups if no space is left, fixes #24052

do not attempt to count resources, since it will be very slow and will be mediaserver specific, so unusable for generic backups, refs #23246

parse folder name instead of modification time which is preserved by rsync, fix return code, fixes #21677