git: openjdk/loom: fibers: fix root cause of MethodExitTest failure

[duke]

Changeset: d7a3e05d
Author:    Serguei Spitsyn <serguei.spitsyn at oracle.com>
Date:      2021-10-25 06:27:37 +0000
URL:       https://git.openjdk.java.net/loom/commit/d7a3e05dccebd74ad8b69b095aae6d4d40a60b51

fix root cause of MethodExitTest failure

! src/hotspot/share/prims/jvm.cpp
! src/java.base/share/classes/java/lang/VirtualThread.java