* forward extra arguments to vcpkg_configure_qmake from submodules
* make image format dependent on tiff and libwebp
* make tools dependent on imageformat
* build options must be passed a bit different then normal qmake options
* add the required dependencies
* a new dependency discovered in qt5-declarative
* need webpdemux also
* qt5-declarative is dependent on imageformats so we can drop it here
* remove empty qt.conf if it exists. closes #8180
* add all recommended dependencies as dependencies in control.