RFR: 8370112: Remove VM_Version::supports_fast_class_init_checks() in platform-specific code [v2]

[David Holmes]

> Please review this simple enhancement to remove runtime checks for `VM_Version::supports_fast_class_init_checks()` in platform specific code, and replace them with asserts - as we know statically whether a given platform supports it.
> 
> The changes are the same for each platform.
> 
> Testing
>  - building all platforms via GHA
>  - tiers 1-3 (sanity)
> 
> Thanks

David Holmes has updated the pull request incrementally with one additional commit since the last revision:

  Remove redundant block

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/29293/files
  - new: https://git.openjdk.org/jdk/pull/29293/files/4d79690f..a721b886

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=29293&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=29293&range=00-01

  Stats: 25 lines in 5 files changed: 0 ins; 5 del; 20 mod
  Patch: https://git.openjdk.org/jdk/pull/29293.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29293/head:pull/29293

PR: https://git.openjdk.org/jdk/pull/29293