RFR: 8265907: JVM crashes when matching VectorMaskCmp Node for Neon backend

[Wang Huang]

* fix the issue JDK-8265907

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Commit messages:
 - 8265907: JVM crashes when matching VectorMaskCmp Node for Neon backend

Changes: https://git.openjdk.java.net/jdk/pull/3670/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3670&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8265907
  Stats: 63 lines in 2 files changed: 63 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3670.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3670/head:pull/3670

PR: https://git.openjdk.java.net/jdk/pull/3670