postmarketos-base: replace elogind suspend hook with sleep-inhibitor

This adds sleep-inhibitor as a dependency when elogind is present, and installs a conf for it with some plugins enabled that are beneficial to devices running pmOS. The elogind suspend hook is dropped.

This resolves issues where suspend is aborted in the hook after PrepareForSleep is sent over dbus (which might cause some things to disable radios/modems, etc for suspend).

The 'period' in the conf is in minutes, a value of 0.1 is 6 seconds, which seems reasonable for releasing the lock when conditions for inhibiting no longer apply, without spinning the CPU too frequently.

Needs on https://gitlab.alpinelinux.org/alpine/aports/-/merge_requests/16072 Merged.