glamor: No need to glFlush before destroying a pixmap.

I assume this was a workaround for an old, broken, closed driver.  The
driver doesn't get to throw away rendering just because the rendering
context's shared-across-processes render target is getting freed from
the local address space.  If the rendering isn't to a shared render
target, then we *do* want to throw away the rendering to it.

Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>

glamor/glamor_egl.c

@@ -609,10 +609,6 @@ glamor_egl_destroy_pixmap_image(PixmapPtr pixmap)
         struct glamor_egl_screen_private *glamor_egl =
             glamor_egl_get_screen_private(scrn);
 
-        /* Before destroy an image which was attached to
-         * a texture. we must call glFlush to make sure the
-         * operation on that texture has been done.*/
-        glamor_block_handler(pixmap->drawable.pScreen);
         eglDestroyImageKHR(glamor_egl->display, pixmap_priv->image);
         pixmap_priv->image = NULL;
     }