RFR: 8357626: RISC-V: Tighten up template interpreter method entry code [v5]

[Anjian Wen]

> do the same thing as x86/AArch64 but for RISCV
> [JDK-8352415](https://bugs.openjdk.org/browse/JDK-8352415) 
> [JDK-8356949](https://bugs.openjdk.org/browse/JDK-8356949)

Anjian Wen has updated the pull request incrementally with one additional commit since the last revision:

  delete the confusing noreg

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/25412/files
  - new: https://git.openjdk.org/jdk/pull/25412/files/ba774e28..81a5e970

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=25412&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=25412&range=03-04

  Stats: 2 lines in 1 file changed: 0 ins; 2 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/25412.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25412/head:pull/25412

PR: https://git.openjdk.org/jdk/pull/25412