Fix the build of OpenCV with XIMEA on Windows 64 bits:

- crosses initializations in "cap_ximea.cpp" (which also contained some awfull "goto" instructions)
  - the "CMAKE_CL_64" variable is not initialized when using mingw

PR#1039 modified to be able to merge on branch 2.4

modules/highgui/CMakeLists.txt

@@ -167,9 +167,9 @@ if(HAVE_XIMEA)
   list(APPEND highgui_srcs src/cap_ximea.cpp)
   ocv_include_directories(${XIMEA_PATH})
   if(XIMEA_LIBRARY_DIR)
-    link_directories(${XIMEA_LIBRARY_DIR})
-  endif()
-  if(CMAKE_CL_64)
+    link_directories("${XIMEA_LIBRARY_DIR}")
+  endif() 
+  if(X86_64)
     list(APPEND HIGHGUI_LIBRARIES m3apiX64)
   else()
     list(APPEND HIGHGUI_LIBRARIES m3api)