[vectorIntrinsics] RFR: 8263417: Add Extract integer nodes implementation for Arm SVE

[Wang Huang]

* Add Extract integer nodes implementation for Arm SVE, like ExtractB/ExtractS/ExtractI/ExtractL
* add `sve_lasta(Register, SIMD_RegVariant, PRegister,  FloatRegister)` & `sve_lastb`

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Commit messages:
 - 8263417: Add Extract integer nodes implementation for Arm SVE

Changes: https://git.openjdk.java.net/panama-vector/pull/48/files
 Webrev: https://webrevs.openjdk.java.net/?repo=panama-vector&pr=48&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8263417
  Stats: 211 lines in 5 files changed: 139 ins; 10 del; 62 mod
  Patch: https://git.openjdk.java.net/panama-vector/pull/48.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-vector pull/48/head:pull/48

PR: https://git.openjdk.java.net/panama-vector/pull/48