Xcode: Suppress same-old warning again.

They changed the wording of it slightly with Xcode 4.

CTestCustom.cmake.in

@@ -42,6 +42,7 @@ SET(CTEST_CUSTOM_WARNING_EXCEPTION
   "warning:.*is.*misused, please use.*"
   "CMakeSetupManifest.xml.*manifest authoring warning.*Unrecognized Element"
   "cc-3968 CC: WARNING File.*" # "implicit" truncation by static_cast
+  "ld: warning: directory not found for option .-(F|L)"
   )
 
 IF(NOT "@CMAKE_GENERATOR@" MATCHES "Xcode")