RFR: 8309129: AArch64: guarantee(T != T2S) failed: "incorrect arrangement" after JDK-8307795

[Chang Peng]

This patch fixes the issue introduced by JDK-8307795. Since addv[1] cannot support "T2S" SIMD arrangement, we should use addp[2] in this case.

TEST passed on AArch64:
hotspot:compiler/vectorapi, jdk:jdk/incubator/vector, tier1-3

[1]: https://developer.arm.com/documentation/ddi0596/2020-12/SIMD-FP-Instructions/ADDV--Add-across-Vector-
[2]: https://developer.arm.com/documentation/ddi0596/2020-12/SIMD-FP-Instructions/ADDP--vector---Add-Pairwise--vector--

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

Commit messages:
 - 8309129: AArch64: guarantee(T != T2S) failed: "incorrect arrangement" after JDK-8307795

Changes: https://git.openjdk.org/jdk/pull/14245/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14245&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8309129
  Stats: 63 lines in 3 files changed: 41 ins; 6 del; 16 mod
  Patch: https://git.openjdk.org/jdk/pull/14245.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14245/head:pull/14245

PR: https://git.openjdk.org/jdk/pull/14245