systemd: iio-sensor-proxy: allow AF_QIPCRTR
QMI protocol over QRTR uses AF_QIPCRTR as address family, allow it in the service file to avoid iio-sensor-proxy crashes. libssc will be fixed in 0.2.0 to handle this lockdown so a proper error code is given instead of an assert for double free on the QMI client, see https://codeberg.org/DylanVanAssche/libssc/issues/25
Send this change to iio-sensor-proxy upstream as well: https://gitlab.freedesktop.org/hadess/iio-sensor-proxy/-/merge_requests/381