mesa: Compare formats using nominal bytes per pixel.

This is a temporary fix which works for the formats we care so far. The
real fix would be abandon the concept "nominal bytes per pixel" entirely
in Mesa, and use macropixels instead, as done in gallium interfaces
already.

src/mesa/state_tracker/st_cb_texture.c

@@ -1417,9 +1417,7 @@ st_finalize_texture(GLcontext *ctx,
           stObj->pt->width[0] != firstImage->base.Width2 ||
           stObj->pt->height[0] != firstImage->base.Height2 ||
           stObj->pt->depth[0] != firstImage->base.Depth2 ||
-          stObj->pt->block.size != cpp ||
-          stObj->pt->block.width != 1 ||
-          stObj->pt->block.height != 1 ||
+          stObj->pt->block.size/stObj->pt->block.width != cpp || /* Nominal bytes per pixel */
           stObj->pt->compressed != firstImage->base.IsCompressed) {
          pipe_texture_release(&stObj->pt);
          ctx->st->dirty.st |= ST_NEW_FRAMEBUFFER;