RFR: 8283728: jdk.hotspot.agent: Wrong location for RISCV64ThreadContext.java

[Christoph Langer]

Fix risv64 -> riscv64

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Commit messages:
 - JDK-8283728

Changes: https://git.openjdk.java.net/jdk/pull/7977/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7977&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8283728
  Stats: 0 lines in 1 file changed: 0 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7977.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7977/head:pull/7977

PR: https://git.openjdk.java.net/jdk/pull/7977