[jdk17u-dev] RFR: 8298472: AArch64: Detect Ampere-1 and Ampere-1A CPUs and set default options

[Patrick Zhang]

Clean backport of CPU detection function for Ampere-1 and Ampere-1A, and performance enhancement with turning on UseSIMDForMemoryOps option for these two CPUs by default. Verified OpenJDK bundled JMH test cases, `make run-test TEST="micro:java.lang.ArrayCopy*"` , SIMD vs NoSIMD ratios are mostly positive as expected, aligned with that on jdk mainline. Low risk to other functions/systems due to the CPU detection logic.

Additional tests done:
1. Linux aarch64 release tier1 on Ampere-1 system, without explicitly specifying UseSIMDForMemoryOps 
2. OpenJDK GHA Sanity Checks on forked repo: https://github.com/cnqpzhang/jdk17u-dev/actions/runs/3919027362

Backport-of: 706845743699efb01994e2d12c65023a3e972b77
Signed-off-by: Patrick Zhang <patrick at os.amperecomputing.com>

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Commit messages:
 - 8298472: AArch64: Detect Ampere-1 and Ampere-1A CPUs and set default options

Changes: https://git.openjdk.org/jdk17u-dev/pull/1067/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1067&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8298472
  Stats: 18 lines in 2 files changed: 15 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1067.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev pull/1067/head:pull/1067

PR: https://git.openjdk.org/jdk17u-dev/pull/1067