vsphere bootstrap: support systemd-resolved in NM prepender

FCOS has switched to systemd-resolved to control nameservers, so DNS_IP should be injected correctly

data/data/bootstrap/vsphere/files/etc/NetworkManager/dispatcher.d/30-local-dns-prepender.template

@@ -6,25 +6,33 @@ case "$STATUS" in
 {{if .PlatformData.VSphere.UserProvidedVIPs}}
     logger -s "NM local-dns-prepender triggered by ${1} ${2}."
     DNS_IP="127.0.0.1"
+    RESOLV="/etc/resolv.conf"
+    NMRESOLV="/var/run/NetworkManager/resolv.conf"
+
+    source /etc/os-release
+    if [[ $NAME == "Fedora" ]]; then
+        RESOLV="/var/run/systemd/resolve/resolv.conf"
+        NMRESOLV="/var/run/systemd/resolve/resolv.conf"
+    fi
 
     # In DHCP connections, the resolv.conf content may be late, thus we wait for nameservers
     timeout 45s /bin/bash <<EOF
 		if [[ "$STATUS" == dhcp* ]]; then
-			logger -s "NM resolv-prepender: Checking for nameservers in /var/run/NetworkManager/resolv.conf"
-			while ! grep nameserver /var/run/NetworkManager/resolv.conf; do
+			logger -s "NM resolv-prepender: Checking for nameservers in ${NMRESOLV}"
+			while ! grep nameserver ${NMRESOLV}; do
 				logger -s "NM resolv-prepender: NM resolv.conf still empty of nameserver"
                 sleep 0.5
             done
         fi
 EOF
     set +e
     logger -s "NM local-dns-prepender: Checking if local DNS IP is the first entry in resolv.conf"
-    if grep nameserver /etc/resolv.conf | head -n 1 | grep -q "$DNS_IP" ; then
+    if grep nameserver ${RESOLV} | head -n 1 | grep -q "$DNS_IP" ; then
         logger -s "NM local-dns-prepender: local DNS IP already is the first entry in resolv.conf"
         exit 0
     else
         logger -s "NM local-dns-prepender: Looking for '# Generated by NetworkManager' in /etc/resolv.conf to place 'nameserver $DNS_IP'"
-        sed -i "/^# Generated by.*$/a nameserver $DNS_IP" /etc/resolv.conf
+        sed -i "/^# Generated by.*$/a nameserver $DNS_IP" ${RESOLV}
     fi
 {{end}}
     ;;