git: openjdk/loom: fibers: Fix fast-path

[duke]

Changeset: 201f78fe
Author:    Ron Pressler <ron.pressler at oracle.com>
Date:      2020-06-02 08:32:38 +0000
URL:       https://git.openjdk.java.net/loom/commit/201f78fe

Fix fast-path

! src/hotspot/cpu/x86/stubGenerator_x86_64.cpp
! src/hotspot/share/runtime/continuation.cpp