ncdu: Update to version 1.18.1

ncdu: Update to version 1.18.1

- Update from 1.17 to 1.18.1
- Update of rootfile not required
- Changelog
    1.18.1 - 2023-02-12
	- Fix build on non-Linux platforms
    1.18 - 2022-12-06
	- Fix 'dark-bg' color scheme to actually have a dark background
	- Backport configuration file support from 2.x
	- Backport many new CLI options from 2.x
	- Negation of existing flags: --no-si, --no-confirm-quit, --no-follow-symlinks, --include-caches, --include-kernfs
	- --[no-]extended in addition to -e
	- --one-file-system and --cross-file-system in addition to -x
	- --slow-ui-updates, --fast-ui-updates in addition to -q
	- Column visibility options: --(show|hide)-(hidden|itemcount|mtime|graph|percent)
	- Sorting: --sort, --[no-]group-directories-first
	- Feature selection: --(enable|disable)-(shell|delete|refresh)
	- Deletion confirmation: --[no-]confirm-delete
	- Hidden file visibility: --show-hidden, --hide-hidden
	- Size display: --apparent-size, --disk-usage

Signed-off-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>