CL: provide a profile dropin for PATH?

[lucab]

Binaries installed via torcx are propagated into their own directory outside of normal path.

I'm currently installing the following /etc/profile.d/torcx-path.sh dropin via ignition:

# torcx drop-in: add torcx-bindir to PATH

export PATH="/var/run/torcx/bin:${PATH}"

But this integration could be improved to let systemd also be aware of it. Another open question is whether this should be prefixed or suffixed on top of existing path?

/cc @dm0-