Link against GLU

Since we use it

BUGS: 426088

CMakeLists.txt

-cmake_minimum_required (VERSION 3.5 FATAL_ERROR)
+cmake_minimum_required (VERSION 3.11 FATAL_ERROR)
 
 set (RELEASE_SERVICE_VERSION_MAJOR "20")
 set (RELEASE_SERVICE_VERSION_MINOR "11")
@@ -45,7 +45,7 @@ include(KDEInstallDirs)
 include(KDECompilerSettings NO_POLICY_SCOPE)
 include(KDECMakeSettings)
 
-if (OPENGL_FOUND)
+if (OPENGL_FOUND AND OPENGL_GLU_FOUND)
      set(OPENGL_SUPPORT true)
 endif()
 

src/CMakeLists.txt

@@ -50,7 +50,7 @@ target_link_libraries(ksudoku
 
 if(OPENGL_SUPPORT)
 target_link_libraries(ksudoku
-	Qt5::OpenGL ${OPENGL_LIBRARIES} ${CMAKE_DL_LIBS}
+	Qt5::OpenGL OpenGL::OpenGL OpenGL::GLU ${CMAKE_DL_LIBS}
 )
 endif(OPENGL_SUPPORT)