[vectorIntrinsics] RFR: 8254826: Add reduction nodes implementation for Arm SVE [v3]

[Dongbo He]

> Contributed-by: <wanghuang3 at huawei.com>, <hexuejin2 at huawei.com>
> 
> Add reduction nodes support for Arm SVE. Add the backend codegen for nodes like "AndReductionVNode" "OrReductionVNode" "XorReductionVNode" "MaxReductionVNode" "MinReductionVNode" .

Dongbo He has updated the pull request incrementally with one additional commit since the last revision:

  remove redundant T_CHAR

-------------

Changes:
  - all: https://git.openjdk.java.net/panama-vector/pull/13/files
  - new: https://git.openjdk.java.net/panama-vector/pull/13/files/87d741fb..8cf45a1f

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=panama-vector&pr=13&range=02
 - incr: https://webrevs.openjdk.java.net/?repo=panama-vector&pr=13&range=01-02

  Stats: 40 lines in 2 files changed: 0 ins; 6 del; 34 mod
  Patch: https://git.openjdk.java.net/panama-vector/pull/13.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-vector pull/13/head:pull/13

PR: https://git.openjdk.java.net/panama-vector/pull/13