androiddeployqt fails with error from qmlimportscanner if qtdeclarative is not installed

If a Qt for Android installation uses only qtbase and no qtdeclarative (no qml folder under the prefix) androiddeployqt will fail with an error from qmlimportscanner not able to find the path <qt_prefix>/qml. This behavior shouldn't happen if no qml folder is present we should just skip instead.