dbus: Fix API break from godbus

Something in godbus seems to have broken API, thus breaking builds
including `go get`.

As an aside, I don't think *this* project should include the Gopkg.toml
file. We should always follow git master automatically. Having said that
I've patched it anyways until we can discuss more.

Author: purpleidea

Gopkg.toml

@@ -4,7 +4,7 @@
 
 [[constraint]]
   name = "github.com/godbus/dbus"
-  version = "4.1.0"
+  version = "5.0"
 
 [prune]
   go-tests = true

dbus/dbus.go

@@ -143,7 +143,7 @@ func NewUserConnection() (*Conn, error) {
 func NewSystemdConnection() (*Conn, error) {
 	return NewConnection(func() (*dbus.Conn, error) {
 		// We skip Hello when talking directly to systemd.
-		return dbusAuthConnection(func() (*dbus.Conn, error) {
+		return dbusAuthConnection(func(opts ...dbus.ConnOption) (*dbus.Conn, error) {
 			return dbus.Dial("unix:path=/run/systemd/private")
 		})
 	})
@@ -201,7 +201,7 @@ func (c *Conn) GetManagerProperty(prop string) (string, error) {
 	return variant.String(), nil
 }
 
-func dbusAuthConnection(createBus func() (*dbus.Conn, error)) (*dbus.Conn, error) {
+func dbusAuthConnection(createBus func(opts ...dbus.ConnOption) (*dbus.Conn, error)) (*dbus.Conn, error) {
 	conn, err := createBus()
 	if err != nil {
 		return nil, err
@@ -221,7 +221,7 @@ func dbusAuthConnection(createBus func() (*dbus.Conn, error)) (*dbus.Conn, error
 	return conn, nil
 }
 
-func dbusAuthHelloConnection(createBus func() (*dbus.Conn, error)) (*dbus.Conn, error) {
+func dbusAuthHelloConnection(createBus func(opts ...dbus.ConnOption) (*dbus.Conn, error)) (*dbus.Conn, error) {
 	conn, err := dbusAuthConnection(createBus)
 	if err != nil {
 		return nil, err