fix /var/run/icecc handling

Was severely broken by 203b51b588fa2e550feeeef73d91e6d72afeafa9.
It first created /var/run/icecc, which was successful and didn't have
the follow-up chown/chmod, so they ended up as root-owned, because
this happened before dropping privileges using libcap-ng. This caused
the later access() check for it to fail, and ended up using the user
path, which however crashed because of there being no $HOME set.
So after every boot, if /var/run was empty, the first launch failed.
All following launches were successful, because the mkdir() failed,
leaving to proper chown/chmod.

Fix by always doing chown/chmod unconditionally. Also do not use
the access() check for detecting if it's the system or user way of launching.