RFR: 8327701: Remove the xlc toolchain [v3]

Tue Mar 12 15:16:30 UTC 2024

> As of [JDK-8325880](https://bugs.openjdk.org/browse/JDK-8325880), building the JDK requires version 17 of IBM Open XL C/C++ (xlc). This is in effect clang by another name, and it uses the clang toolchain in the JDK build. Thus the old xlc toolchain is no longer supported, and should be removed.

Magnus Ihse Bursie has updated the pull request incrementally with two additional commits since the last revision:

 - Set JVM_PICFLAG="-fpic -mcmodel=large" for AIX
 -  Open XL 17.1.1.4 is clang 15.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/18172/files
  - new: https://git.openjdk.org/jdk/pull/18172/files/53a05019..e7949499

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=18172&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18172&range=01-02

  Stats: 7 lines in 3 files changed: 4 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/18172.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18172/head:pull/18172

PR: https://git.openjdk.org/jdk/pull/18172