qmake fails to create TARGET_plugin_import.cpp and TARGET_qml_plugin_import.cpp when target is lib instead of app and the build of Qt is static

5.7 fixed a lot of problems related with qml module imports with static builds of Qt. These seem to be fixed for app templates but not for lib templates. I have a project that generates a lib with a static build of Qt and qmake doesn't generate TARGET_plugin_import.cpp and TARGET_qml_plugin_import.cpp, therefore I have to manually declare all the plugin imports on the code and initialize them by myself.