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

[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

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

Commit messages:
 - 8337421: RISC-V: client VM build failure after JDK-8335191

Changes: https://git.openjdk.org/jdk/pull/20386/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20386&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8337421
  Stats: 200 lines in 2 files changed: 100 ins; 99 del; 1 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