[jdk13u-dev] RFR: 8252051: Make mlvmJvmtiUtils strncpy uses GCC 10.x friendly

[Yuri Nesterenko]

low-risk necessary fix for gcc10. Works fine to me.

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Commit messages:
 - Backport 51a3b25d71e0e5875ac4bd2e76dfc2f9595dd83f

Changes: https://git.openjdk.org/jdk13u-dev/pull/400/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk13u-dev&pr=400&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8252051
  Stats: 6 lines in 1 file changed: 3 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk13u-dev/pull/400.diff
  Fetch: git fetch https://git.openjdk.org/jdk13u-dev pull/400/head:pull/400

PR: https://git.openjdk.org/jdk13u-dev/pull/400