vala-dbus-binding-tool: fix the version inside the package

* "vala-dbus-binding-tool_version" string ends as the version and e.g. libfso-glib doesn't like it at all
  | configure: error: Package requirements (vala-dbus-binding-tool-1.0 >= 0.4.0) were not met:
  | Requested 'vala-dbus-binding-tool-1.0 >= 0.4.0' but version of Vala-DBus-Binding-Tool is vala-dbus-binding-tool_version

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>