RFR: 8350723: RISC-V: debug.cpp help() is missing riscv line for pns

[SendaoYan]

Hi all,

This PR add RISC-V entry line for pns() call in src/hotspot/share/utilities/debug.cpp file. This will be useful when call help() function in gdb. No risk.

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Commit messages:
 - 8350723: RISC-V: debug.cpp help() is missing riscv line for pns

Changes: https://git.openjdk.org/jdk/pull/23793/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=23793&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8350723
  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/23793.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23793/head:pull/23793

PR: https://git.openjdk.org/jdk/pull/23793