bundles/{radvd,wide-dhcp6c}: improve handling of non-properly terminated ip-down scripts

bundles/pppd/files/pppoe.service

@@ -7,6 +7,8 @@ Type=oneshot
 RemainAfterExit=true
 ExecStart=/usr/bin/pon
 ExecStop=/usr/bin/poff -a
+# This is important, because otherwise systemd will kill the ip-down scripts!
+KillMode=none
 
 [Install]
 WantedBy=default.target

bundles/radvd/files/ip-up

@@ -1,3 +1,8 @@
 #!/bin/bash
 
-systemctl start radvd
+if systemctl is-active wide-dhcpv6-client;
+then
+    systemctl restart radvd
+else
+    systemctl start radvd
+fi

bundles/wide-dhcp6c/files/ip-up

@@ -8,4 +8,9 @@ then
     exit 0
 fi
 
-systemctl start wide-dhcpv6-client
+if systemctl is-active wide-dhcpv6-client;
+then
+    systemctl restart wide-dhcpv6-client
+else
+    systemctl start wide-dhcpv6-client
+fi