RFR: 8349088: De-virtualize Codeblob and nmethod [v6]

[Vladimir Kozlov]

> Remove virtual methods from CodeBlob and nmethod to simplify saving/restoring in Leyden AOT cache. It avoids the need to patch hidden VPTR pointer to class's virtual table.
> 
> Added C++ static asserts to make sure no virtual methods are added in a future.
> 
> Fixed/cleaned SA code which process CodeBlob and its subclasses. Use `CodeBlob::_kind` field value to determine the type of blob.
> 
> Tested tier1-5, hs-tier6-rt (for JFR testing), stress, xcomp

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

  Fix Zero VM build

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/23533/files
  - new: https://git.openjdk.org/jdk/pull/23533/files/1d108349..b09ddce6

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23533&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23533&range=04-05

  Stats: 11 lines in 2 files changed: 7 ins; 1 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/23533.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23533/head:pull/23533

PR: https://git.openjdk.org/jdk/pull/23533