XIMEA cam support: use correct library for 64 bit Linux

modules/highgui/CMakeLists.txt

@@ -165,11 +165,13 @@ endif(HAVE_opencv_androidcamera)
 
 if(HAVE_XIMEA)
   list(APPEND highgui_srcs src/cap_ximea.cpp)
-  ocv_include_directories(${XIMEA_PATH})
+  if(XIMEA_PATH)
+    ocv_include_directories(${XIMEA_PATH})
+  endif()
   if(XIMEA_LIBRARY_DIR)
     link_directories("${XIMEA_LIBRARY_DIR}")
   endif()
-  if(X86_64)
+  if(WIN32 AND X86_64)
     list(APPEND HIGHGUI_LIBRARIES m3apiX64)
   else()
     list(APPEND HIGHGUI_LIBRARIES m3api)