quick if test so one can just synlink trunk uplinks using qemu-ifup-TRUNKNAME syntax and be done with it

files/qemu-ifup

@@ -6,6 +6,10 @@ if [ ${#IFACE} -gt 15 ]; then
    echo "interface name too long, mac 14 char: $IFACE"
    exit 10
 fi
+if [[ ${0##*/} == qemu-ifup-* ]]; then
+   PARENTIF="${0##*-}"
+   echo "legacy VLAN trunk mode using $PARENTIF as uplink"
+fi
 
 VNI=$(printf '%d' $((16#${IFACE##*.})))