Revert "[kcms/cursor] Port to required properties"
We can not use the required properties, because it breaks the property binding. https://github.com/qt/qtdeclarative/commit/ec79af7396fd695b25f8f7dba66e8048d54b953b apparently fixes that, however it is not released as part of Qt6 or is part of the KDE patch collection. This reverts commit f3293bc5. BUG: 453226