VAAPI-XCB: Close X11 connection only in VAAPI-XCB and not in decoder (workaround for ATI/AMD GPU)

On AMD/ATI the X11 connection is shared between the decoding and displaying thread. Therefor close it only once. This is a workaround and might break NVIDIA GPU's.

modules/codec/avcodec/vaapi.c

@@ -575,9 +575,10 @@ static void Close( vlc_va_vaapi_t *p_va )
 
         vlc_va_Terminate( p_va->conn );
     }
-
+#if 0 /* FIXME: workaround for ATI and AMD graphics GPU */
     if( p_va->display )
         XCloseDisplay( p_va->display );
+#endif
 }
 
 static void Delete( vlc_va_t *p_external )