RFR: 8357396: Refactor nmethod::make_not_entrant to use Enum instead of "const char*" [v2]

[Cesar Soares Lucas]

> Please review this refactor to transform the reasons for making an nmethod not entrant from `const char*` into enum values.
> 
> Tested on Linux x64 with JTREG tier1-3 in fastdebug and release mode.

Cesar Soares Lucas has updated the pull request incrementally with one additional commit since the last revision:

  Address PR feedback: modify emum to be scoped.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/25338/files
  - new: https://git.openjdk.org/jdk/pull/25338/files/933b958d..b3bb4365

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=25338&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=25338&range=00-01

  Stats: 83 lines in 13 files changed: 55 ins; 4 del; 24 mod
  Patch: https://git.openjdk.org/jdk/pull/25338.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25338/head:pull/25338

PR: https://git.openjdk.org/jdk/pull/25338