RFR: 8329141: Obsolete RTM flags and code [v2]

[Vladimir Kozlov]

> Obsolete HotSpot RTM flags which were deprecated in JDK 23.
> RTM related VM code and tests were removed.
> 
> Tested tier1-3,stress,xcomp

Vladimir Kozlov has updated the pull request incrementally with one additional commit since the last revision:

  Addressed comments, removed Opaque3 node which is now unused

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/19589/files
  - new: https://git.openjdk.org/jdk/pull/19589/files/fcfb62fd..45f8e73c

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=19589&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=19589&range=00-01

  Stats: 39 lines in 6 files changed: 0 ins; 37 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/19589.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19589/head:pull/19589

PR: https://git.openjdk.org/jdk/pull/19589