* [assimp] Update to 5.3.0
* Remove <utf8.h> from public include
* [assimp] fix pkg-config for static builds
* [qt5-3d] Use pkgconfig to find assimp
* [assimp] -llibassimp -> -lassimp
* [assimp] Update to 5.3.1
* [assimp] Fix -config.cmake files
* [assimp] Fix linux build and provide backwards-compatible alias
* [assimp][irrxml][kubazip][poly2tri][polyclipping] Extract vendored dependencies
* [assimp] Use find_dependency(); add ZLIB dependency
* [polyclipping] Do not suffix upstream binaries
Co-authored-by: Robert Schumacher <roschuma@microsoft.com>
Co-authored-by: Stefano Sinigardi <stesinigardi@hotmail.com>