RFR: 8310873: Re-enable locked_create_entry symbol check in runtime/NMT/CheckForProperDetailStackTrace.java for RISC-V

[Feilong Jiang]

The `Platform.isRISCV64()` check was once added in our internal development. The reason was that we have different C Frame and Java Frame layouts at first. So we could not get the right stacks without the RISC-V specific `get_native_stack`. After defining RISC-V related `get_native_stack` method (refactored by https://github.com/openjdk/jdk-sandbox/commit/db2415748747a0912749bb8fc160a8948021a924), it could return the expected symbols. So we can remove the platform check for RISC-V safely.

runtime/NMT/CheckForProperDetailStackTrace.java still passed without `Platform.isRISCV64()`.

Testing:
- [x] fastdebug  build (cross/native compile)
- [x] release  build (cross/native compile)

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Commit messages:
 - Re-enable locked_crate_entry symbol check for RISC-V

Changes: https://git.openjdk.org/jdk/pull/14650/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14650&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8310873
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/14650.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14650/head:pull/14650

PR: https://git.openjdk.org/jdk/pull/14650