Adapt build system for building against qt6

CMakeLists.txt

@@ -13,7 +13,7 @@ set(KMINES_VERSION "${KMINES_BASE_VERSION}.${RELEASE_SERVICE_COMPACT_VERSION}")
 project(kmines VERSION ${KMINES_VERSION})
 
 set(QT_MIN_VERSION "5.15.0")
-set(KF5_MIN_VERSION "5.85.0")
+set(KF5_MIN_VERSION "5.89.0")
 
 find_package(ECM ${KF5_MIN_VERSION} REQUIRED CONFIG)
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${ECM_MODULE_PATH})
@@ -28,7 +28,7 @@ include(ECMQtDeclareLoggingCategory)
 include(ECMSetupVersion)
 include(FeatureSummary)
 
-find_package(Qt5 ${QT_MIN_VERSION} REQUIRED NO_MODULE COMPONENTS Widgets)
+find_package(Qt${QT_MAJOR_VERSION} ${QT_MIN_VERSION} REQUIRED NO_MODULE COMPONENTS Widgets)
 find_package(KF5 ${KF5_MIN_VERSION} REQUIRED COMPONENTS
     Config
     ConfigWidgets