8379016: Improve double_keccak() intrinsic on ARM when SHA3 instructions are not available

[smemery]

This enhancement provides AArch64 GPR intrinsics for doubleKeccak(). Previously, only SIMD (Neon) intrinsics were implemented for doubleKeccak() on AArch64 systems. Performance gains for ML-KEM and ML-DSA benchmarks improve 2 to 9% with the GPR intrinsics.

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Issue

• JDK-8379016: Improve double_keccak() intrinsic on ARM when SHA3 instructions are not available (Enhancement - P3)

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