RFR: 8352218: RISC-V: Zvfh requires RVV [v5]

[Robbin Ehn]

> Hi please consider.
> 
> Added case to turn off UseZvfh when no RVV. 
> Which is the cause of the test issues, zvfh on but no rvv.
> 
> Also made all case identical and added no warning when default.
> Move them to the common init, as the "UseExtension" is not C2 specific.
> 
> Manual tested and some random compiler tests.
> 
> Thanks, Robbin

Robbin Ehn has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 10 commits:

 - Spell fix
 - Merge branch 'master' into maxvector_0
 - dep check
 - Merge branch 'master' into maxvector_0
 - Merge branch 'master' into maxvector_0
 - Merge branch 'master' into maxvector_0
 - hwprobe deps
 - Merge branch 'master' into maxvector_0
 - Moved to common
 - Disable UseZvfh when no RVV

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

Changes: https://git.openjdk.org/jdk/pull/24094/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24094&range=04
  Stats: 106 lines in 2 files changed: 45 ins; 19 del; 42 mod
  Patch: https://git.openjdk.org/jdk/pull/24094.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24094/head:pull/24094

PR: https://git.openjdk.org/jdk/pull/24094