ecore_buffer: Remove duplicate function calls

As we already set these variables at the top of the function, there is
no need to reget the xcb connection or generate the pixmap id.

src/modules/ecore_buffer/x11_dri3/ecore_buffer_x11_dri3.c

@@ -331,11 +331,9 @@ _dri3_pixmap_from_fd(Ecore_X_Display *dpy, Ecore_X_Drawable draw, int width, int
    if (!dpy)
      return 0;
 
-   c = XGetXCBConnection(dpy);
    if (!c)
      return 0;
 
-   pixmap = xcb_generate_id(c);
    if (!pixmap)
      return 0;