Fixed linux compilation problem.

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/trunk@12631 178a84e3-b1eb-0310-8ba1-8eac791a3b58

src/graphics/irr_driver.cpp

@@ -567,6 +567,7 @@ bool IrrDriver::moveWindow(const int x, const int y)
         return false;
     }
 #elif defined(__linux__) && !defined(ANDROID)
+    const SExposedVideoData& videoData = m_video_driver->getExposedVideoData();
     using namespace X11;
 
     // TODO: Actually handle possible failure