Add autosuspend rules for emulated QEMU devices

This effectively partially reverts "rules: remove all power management from
udev" / e2452eef. The rules for emulated QEMU
hardware were removed in one fell swoop with other rules which were causing
problems. But the qemu rules were working properly (and were adjusted through
patches over time). Nowadays we have a hwdb for this, so add hwdb entries using
the new detailed modalias.

https://github.com/systemd/systemd/pull/353#issuecomment-658810289