RFR: JDK-8308300: enhance exceptions in MappedMemoryUtils.c [v2]

[Matthias Baesken]

> MappedMemoryUtils.c can generate exceptions like those :
> java.io.UncheckedIOException: java.io.IOException: Invalid argument
>        at java.base/java.nio.MappedMemoryUtils.force(MappedMemoryUtils.java:105)
>        at java.base/java.nio.Buffer$2.force(Buffer.java:890)
>        at java.base/jdk.internal.misc.ScopedMemoryAccess.forceInternal(ScopedMemoryAccess.java:317)
>        at java.base/jdk.internal.misc.ScopedMemoryAccess.force(ScopedMemoryAccess.java:305)
>        at java.base/jdk.internal.foreign.MappedMemorySegmentImpl.force(MappedMemorySegmentImpl.java:92)
>        at TestByteBuffer.testMappedSegmentAsByteBuffer(TestByteBuffer.java:327)
> 
> (we see this for example on AIX); there is some room for improvement, at least the info should be added that msync failed and caused this exception.

Matthias Baesken has updated the pull request incrementally with one additional commit since the last revision:

  Change comments and madvise exception text

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/14054/files
  - new: https://git.openjdk.org/jdk/pull/14054/files/5e800075..7b9ecc22

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=14054&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=14054&range=00-01

  Stats: 6 lines in 2 files changed: 0 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/14054.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14054/head:pull/14054

PR: https://git.openjdk.org/jdk/pull/14054