RFR: 8337421: RISC-V: client VM build failure after JDK-8335191 [v2]

[Gui Cao]

> Hi, please help review this patch that fix the client VM build failed for riscv.
> 
> Error log for client VM build to see: [JDK-8337421](https://bugs.openjdk.org/browse/JDK-8337421)
> 
> The root cause is that MaxVectorSize is defined in COMPILER2 or JVMCI, which is not included in client mode. In addition to this, I have adjusted the functions related to initialization using UseSHA256Intrinsics, UseSHA512Intrinsics, UseMD5Intrinsics, UseChaCha20Intrinsics, UseSHA1Intrinsics, UseAdler32Intrinsics to be under the control of the COMPILER2 macro.  And made related adjustments in VM_Version::c2_initialize().
> 
> ### Testing
> - [x] linux-riscv client VM fastdebug native build

Gui Cao has updated the pull request incrementally with one additional commit since the last revision:

  Fix for review comments

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/20386/files
  - new: https://git.openjdk.org/jdk/pull/20386/files/6f8b6883..d9055e6f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=20386&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=20386&range=00-01

  Stats: 14 lines in 2 files changed: 9 ins; 5 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/20386.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20386/head:pull/20386

PR: https://git.openjdk.org/jdk/pull/20386