qtsafercctool fails to build with Qt 5.15

22:12:31 | /home/qt/work/build/tmp/work/x86_64-linux/qtsaferenderer-native/1.1.2-r0/git/tools/qtsafercctool/rcc.cpp: In member function ‘bool RCCResourceLibrary::addFile(const QString&, const RCCFileInfo&)’:
22:12:31 | /home/qt/work/build/tmp/work/x86_64-linux/qtsaferenderer-native/1.1.2-r0/git/tools/qtsafercctool/rcc.cpp:629:24: error: ‘class QHash<QString, RCCFileInfo*>’ has no member named ‘insertMulti’; did you mean ‘insert’?
22:12:31 |      parent->m_children.insertMulti(filename, s);
22:12:31 |                         ^~~~~~~~~~~
22:12:31 |                         insert