[vectorIntrinsics] RFR: 8259536: Add cast nodes between interger types implementation for Arm SVE

[Wang Huang]

This patch add cast nodes between interger types implementation for Arm SVE like  "VectorCastB2X" "VectorCastI2X " "VectorCastS2X" "VectorCastL2X".

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Commit messages:
 - 8259536: Add cast nodes between interger types implementation for Arm SVE

Changes: https://git.openjdk.java.net/panama-vector/pull/31/files
 Webrev: https://webrevs.openjdk.java.net/?repo=panama-vector&pr=31&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8259536
  Stats: 243 lines in 3 files changed: 233 ins; 10 del; 0 mod
  Patch: https://git.openjdk.java.net/panama-vector/pull/31.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-vector pull/31/head:pull/31

PR: https://git.openjdk.java.net/panama-vector/pull/31