iris: Drop vestiges of throttling code

src/gallium/drivers/iris/iris_batch.c

@@ -345,11 +345,7 @@ create_batch(struct iris_batch *batch)
 static void
 iris_batch_reset(struct iris_batch *batch)
 {
-   if (batch->last_bo != NULL) {
-      iris_bo_unreference(batch->last_bo);
-      batch->last_bo = NULL;
-   }
-   batch->last_bo = batch->bo;
+   iris_bo_unreference(batch->bo);
    batch->primary_batch_size = 0;
    batch->contains_draw = false;
 
@@ -381,8 +377,6 @@ iris_batch_free(struct iris_batch *batch)
    batch->map = NULL;
    batch->map_next = NULL;
 
-   iris_bo_unreference(batch->last_bo);
-
    iris_destroy_hw_context(bufmgr, batch->hw_ctx_id);
 
    _mesa_hash_table_destroy(batch->cache.render, NULL);
@@ -552,8 +546,6 @@ _iris_batch_flush(struct iris_batch *batch, const char *file, int line)
 
    int ret = submit_batch(batch);
 
-   //throttle(iris);
-
    if (ret >= 0) {
       //if (iris->ctx.Const.ResetStrategy == GL_LOSE_CONTEXT_ON_RESET_ARB)
          //iris_check_for_reset(ice);

src/gallium/drivers/iris/iris_batch.h

@@ -62,9 +62,6 @@ struct iris_batch {
    /** Size of the primary batch if we've moved on to a secondary. */
    unsigned primary_batch_size;
 
-   /** Last BO submitted to the hardware.  Used for glFinish(). */
-   struct iris_bo *last_bo;
-
    /** Last Surface State Base Address set in this hardware context. */
    uint64_t last_surface_base_address;