[vectorIntrinsics] RFR: 8263417: Add Extract integer nodes implementation for Arm SVE [v2]

[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`

Wang Huang has updated the pull request incrementally with one additional commit since the last revision:

  replace tmp with rscratch

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Changes:
  - all: https://git.openjdk.java.net/panama-vector/pull/48/files
  - new: https://git.openjdk.java.net/panama-vector/pull/48/files/4d3840a8..c3c9f871

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=panama-vector&pr=48&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=panama-vector&pr=48&range=00-01

  Stats: 42 lines in 2 files changed: 0 ins; 0 del; 42 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