RFR: JDK-8313616: support loading library members on AIX in os::dll_load [v2]

[Matthias Baesken]

> AIX dlopen allows loading members of a lib; the syntax for members is libname(member-object) . However this needs an additional flag RTLD_MEMBER passed to dlopen.
> Example from our OpenJDK codebase : dlopen("/usr/lib/libperfstat.a(shr_64.o)", RTLD_MEMBER | RTLD_NOW);
> 
> However, currently we do not support this in os::dll_load, so member loading would fail because of the missing RTLD_MEMBER flag.
> See https://www.ibm.com/docs/en/aix/7.1?topic=d-dlopen-subroutine part about RTLD_MEMBER

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

  adjust adding dlflag

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/15204/files
  - new: https://git.openjdk.org/jdk/pull/15204/files/604378b0..4f79edc6

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=15204&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=15204&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/15204.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15204/head:pull/15204

PR: https://git.openjdk.org/jdk/pull/15204