AB#2114 Add QEMU metadata API (#237)

* Add QEMU metadata API

* API server is started automatically when using terraform to deploy a QEMU cluster

* Enable QEMU metadata usage for disk-mapper, debugd and the Coordinator

Signed-off-by: Daniel Weiße <dw@edgeless.systems>

hack/qemu-metadata-api/virtwrapper/virtwrapper.go

@@ -0,0 +1,32 @@
+package virtwrapper
+
+import "libvirt.org/go/libvirt"
+
+type Connect struct {
+	Conn *libvirt.Connect
+}
+
+func (c *Connect) LookupNetworkByName(name string) (*Network, error) {
+	net, err := c.Conn.LookupNetworkByName(name)
+	if err != nil {
+		return nil, err
+	}
+	return &Network{Net: net}, nil
+}
+
+type Network struct {
+	Net virNetwork
+}
+
+func (n *Network) GetDHCPLeases() ([]libvirt.NetworkDHCPLease, error) {
+	return n.Net.GetDHCPLeases()
+}
+
+func (n *Network) Free() {
+	_ = n.Net.Free()
+}
+
+type virNetwork interface {
+	GetDHCPLeases() ([]libvirt.NetworkDHCPLease, error)
+	Free() error
+}