fix(run/openrc): truncate runtime directory before starting Anubis (#1122)

If Anubis is not shut down correctly and there are leftover socket
files, Anubis will refuse to start.

As "checkpath -D" currently does not work as expected
(https://github.com/OpenRC/openrc/issues/335), simply use "rm -rf"
before starting Anubis.

Signed-off-by: Anna @CyberTailor <cyber@sysrq.in>

run/openrc/anubis.initd

@@ -30,5 +30,6 @@ start_pre() {
 		return 1
 	fi
 
-	checkpath -d -o "${command_user?}" "/run/anubis_${instance?}"
+	rm -rf "/run/anubis_${instance?}"
+	checkpath -D -o "${command_user?}" "/run/anubis_${instance?}"
 }