zink: only update usage on buffer rebind if rebinds occurred

this is a harmless case, but it's still wrong

cc: mesa-stable

Reviewed-by: Dave Airlie <airlied@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15429>

src/gallium/drivers/zink/zink_context.c

@@ -3926,7 +3926,8 @@ rebind_buffer(struct zink_context *ctx, struct zink_resource *res, uint32_t rebi
       }
    }
 end:
-   zink_batch_resource_usage_set(&ctx->batch, res, has_write);
+   if (num_rebinds)
+      zink_batch_resource_usage_set(&ctx->batch, res, has_write);
    return num_rebinds;
 }