[vectorIntrinsics] RFR: 8259536: Add cast nodes between interger types implementation for Arm SVE [v4]

[Wang Huang]

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

Wang Huang has updated the pull request incrementally with two additional commits since the last revision:

 - remove useless codes
 - remove walkaround codes

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Changes:
  - all: https://git.openjdk.java.net/panama-vector/pull/31/files
  - new: https://git.openjdk.java.net/panama-vector/pull/31/files/2a6df4e1..95fbbb7e

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=panama-vector&pr=31&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=panama-vector&pr=31&range=02-03

  Stats: 15 lines in 1 file changed: 0 ins; 15 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