ERR: Fix test to use post CMAKE_X_LIBS variables

Tests/X11/CMakeLists.txt

@@ -2,11 +2,12 @@
 PROJECT (UseX11 C)
 
 INCLUDE (${CMAKE_ROOT}/Modules/FindX11.cmake)
+MESSAGE("X11_FOUND: ${X11_FOUND}")
 
 ADD_EXECUTABLE (UseX11 X11.c)
 
-IF(CMAKE_HAS_X)
+IF(X11_FOUND)
   ADD_DEFINITIONS(-DCMAKE_HAS_X)
   INCLUDE_DIRECTORIES(${X11_INCLUDE_DIR})
-  TARGET_LINK_LIBRARIES(UseX11 ${CMAKE_X_LIBS})
-ENDIF(CMAKE_HAS_X)
+  TARGET_LINK_LIBRARIES(UseX11 ${X11_LIBRARIES})
+ENDIF(X11_FOUND)