gl: Remove optimization that does the wrong thing

Drawing a texture-scale node like a texture node when the filter is set
to "linear" doesn't work, because the texture node switches to
trilinear when mipmaps are available.

gsk/gl/gskglrenderjob.c

@@ -3784,12 +3784,6 @@ gsk_gl_render_job_visit_texture_scale_node (GskGLRenderJob      *job,
   GskTextureKey key;
   guint texture_id;
 
-  if (filter == GSK_SCALING_FILTER_LINEAR)
-    {
-      gsk_gl_render_job_visit_texture (job, texture, bounds);
-      return;
-    }
-
   gsk_gl_render_job_untransform_bounds (job, &job->current_clip->rect.bounds, &clip_rect);
 
   if (!graphene_rect_intersection (bounds, &clip_rect, &clip_rect))