syncqt is not found when building qt submodules using cmake >= 3.29

CMake 3.29 doesn't generate the PACKAGE_PREFIX_DIR anymore in Config.cmake files, but configure-time syncqt still relies on PACKAGE_PREFIX_DIR in the Qt6CoreToolsAdditionalTargetInfo.cmake. We should replace the PACKAGE_PREFIX_DIR with the reverse calculated one.
Steps to reproduce with CMake versions >= 3.29

mkdir build_qtbase
cd buid_qtbase
path-to/qt6/qtbase/configure -developer-build -nomake tests -nomake examples
ninja
cd ..
mkdir build_qt<module_name>
cd  build_qt<module_name>
../build_qtbase/bin/qt-configure-module path-to/qt6/qt<module_name>