hg: jdk/jdk: 8239129: ZGC: Allow -XX:AllocateHeapAt to use any filesystem

[per.liden at oracle.com]

Changeset: d6dd48a23a72
Author:    pliden
Date:      2020-02-24 13:52 +0100
URL:       https://hg.openjdk.java.net/jdk/jdk/rev/d6dd48a23a72

8239129: ZGC: Allow -XX:AllocateHeapAt to use any filesystem
Reviewed-by: stefank, pliden, ysuenaga
Contributed-by: yasuenag at gmail.com, per.liden at oracle.com

! src/hotspot/os/linux/gc/z/zPhysicalMemoryBacking_linux.cpp
+ test/hotspot/jtreg/gc/z/TestAllocateHeapAt.java