Allow for libvirt's socket activation

Now that we're using polkit by default having the rw socket mode 0777 is
fine.

debian/rules

@@ -177,10 +177,6 @@ endif
 	# Don't ship api files in the daemon package
 	rm -r debian/libvirt-daemon/usr/share/libvirt/api/
 
-	# Don't ship the socket activation file until we switched to polkit
-	# and we can therefore ignore socket permissions (#762606)
-	rm -f debian/*/lib/systemd/system/libvirtd.socket
-
 override_dh_installinit:
 	dh_systemd_enable
 	dh_installinit -p libvirt-daemon-system --name=libvirtd --restart-after-upgrade -- defaults 28 72