[mips][builtins] Streamline the construct stubs

Port: 366d30c9

Change-Id: I8cb720b7de38344627818c578efc36f42c33bbcb
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2531367Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Auto-Submit: Liu yu <liuyu@loongson.cn>
Cr-Commit-Position: refs/heads/master@{#71105}