Merge branch 'log4qt-install-step-is-optional'

* log4qt-install-step-is-optional:
  Use Log4Qt_INCLUDE_DIRS and Log4Qt_LIBRARIES specified in LogQtConfig

CMakeExternals/Log4Qt.cmake

@@ -44,7 +44,7 @@ IF(${add_project})
   
   LIST(APPEND CTK_SUPERBUILD_EP_ARGS -DLog4Qt_DIR:PATH=${Log4Qt_DIR})
 
-  SET(${Log4Qt_enabling_variable}_INCLUDE_DIRS Log4Qt_INCLUDE_DIR)
+  SET(${Log4Qt_enabling_variable}_INCLUDE_DIRS Log4Qt_INCLUDE_DIRS)
   SET(${Log4Qt_enabling_variable}_FIND_PACKAGE_CMD Log4Qt)
 
 ENDIF()

Plugins/org.commontk.log4qt/target_libraries.cmake

@@ -6,5 +6,5 @@
 
 SET(target_libraries
   CTKPluginFramework
-  Log4Qt
+  Log4Qt_LIBRARIES
 )