git: openjdk/loom: fibers: Minor tweaks

[duke]

Changeset: 258aac65
Author:    Ron Pressler <ron.pressler at oracle.com>
Date:      2021-08-19 14:06:36 +0000
URL:       https://git.openjdk.java.net/loom/commit/258aac65f5ff4188406e8856b72d06cf7f06e7b7

Minor tweaks

! src/hotspot/share/oops/instanceStackChunkKlass.cpp
! src/hotspot/share/runtime/stubRoutines.cpp
! src/hotspot/share/runtime/stubRoutines.hpp
! src/hotspot/share/runtime/thread.cpp