Installation instructions need enhancement for non-systemd systems
Hi,

i try to compile and install the latest master branch of box64 on a non-systemd Linux (Void Linux, aarch64, glibc variant).

`make` & `make install` work fine, but i don't know how to update binfmt on such systems.

The [installation instructions](https://github.com/ptitSeb/box64/blob/main/docs/COMPILE.md) say to issue the `sudo systemctl restart systemd-binfmt` command, but of course this won't work on non-systemd systems.

Could you please update the installation instructions?