RFR: 8315195: RISC-V: Update hwprobe query for new extensions [v2]

[Robbin Ehn]

> Hi all, please consider.
> 
> Linux 6.5 added new extensions to hwprobe.
> Manually tested with qemu patch: https://lists.nongnu.org/archive/html/qemu-devel/2023-08/msg04784.html
> And https://bugs.openjdk.org/browse/JDK-8315206 applied.
> 
> Also cleanup vendor path, the goal is to only have vendor specific extension in vendor paths.
> But since we also have older kernels we need to support them also.
> 
> Thanks!

Robbin Ehn has updated the pull request incrementally with one additional commit since the last revision:

  pre-6.5 kernel support

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/15465/files
  - new: https://git.openjdk.org/jdk/pull/15465/files/8a839aac..b59da11f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=15465&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=15465&range=00-01

  Stats: 5 lines in 1 file changed: 5 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/15465.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15465/head:pull/15465

PR: https://git.openjdk.org/jdk/pull/15465