gl/dispmanx: assign render_rect to window before window_resize

If the `render_rect` for a dispmanx display is set after calling
`window_resize` the resize defaults to the dp_width and dp_height to
determine the location of the render rectangle instead of the correct
dimensions that should be set on the window_egl.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-base/-/merge_requests/1056>

gst-libs/gst/gl/dispmanx/gstglwindow_dispmanx_egl.c

@@ -310,9 +310,8 @@ _set_render_rectangle (gpointer data)
   GST_LOG_OBJECT (render->window_egl, "setting render rectangle %i,%i+%ix%i",
       render->rect.x, render->rect.y, render->rect.w, render->rect.h);
 
-  window_resize (render->window_egl, render->rect.w, render->rect.h, TRUE);
-
   render->window_egl->render_rect = render->rect;
+  window_resize (render->window_egl, render->rect.w, render->rect.h, TRUE);
 }
 
 static gboolean