[jdk17u-dev] RFR: 8339248: RISC-V: Remove li64 macro assembler routine and related code

[Gui Cao]

Hi, The same issue also exists in jdk17u. So I would like to backport [JDK-8339248](https://bugs.openjdk.org/browse/JDK-8339248) to jdk17u-dev. with this patch ,it will save us some unnecessary runtime checks. This is a risc-v specific change, risk is low.

### Testing
- [x] Run hotspot:tier1 tests on SOPHON SG2042 (release)

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Commit messages:
 - Backport 8339248: RISC-V: Remove li64 macro assembler routine and related code

Changes: https://git.openjdk.org/jdk17u-dev/pull/2842/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2842&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8339248
  Stats: 111 lines in 4 files changed: 0 ins; 111 del; 0 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/2842.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/2842/head:pull/2842

PR: https://git.openjdk.org/jdk17u-dev/pull/2842