IPv6 DHCP

configs/releng/airootfs/etc/systemd/network/20-{ethernet,wirless}.network:
Making sure that systemd-networkd enables DHCP capabilities also for
IPv6 ('DHCP=yes' and unsetting IPv6AcceptRA - see `man 5
systemd.network` for further information).

Closes #23

configs/releng/airootfs/etc/systemd/network/20-ethernet.network

@@ -3,9 +3,8 @@ Name=en*
 Name=eth*
 
 [Network]
-DHCP=ipv4
+DHCP=yes
 IPv6PrivacyExtensions=yes
-IPv6AcceptRA=false
 
 [DHCP]
 RouteMetric=512

configs/releng/airootfs/etc/systemd/network/20-wireless.network

@@ -3,9 +3,8 @@ Name=wlp*
 Name=wlan*
 
 [Network]
-DHCP=ipv4
+DHCP=yes
 IPv6PrivacyExtensions=yes
-IPv6AcceptRA=false
 
 [DHCP]
 RouteMetric=1024