8353686: Optimize Math.cbrt for x86 64 bit platforms

[missa-prime]

The goal of this PR is to implement an x86_64 intrinsic for java.lang.Math.cbrt() using libm.

The results of all tests posted below were captured with an Intel® Xeon 6761P using OpenJDK v25-b15 as the baseline version.

For performance data collected with the built in cbrt micro-benchmark, see the table below. Each result is the mean of 8 individual runs. Overall, the intrinsic provides a performance uplift of 41%.

Benchmark	Throughput with baseline (op/s)	Throughput with intrinsic (op/s)	Speedup
MathBench.cbrt	148242	209122	1.41x

Finally, the jtreg:test/jdk/java/lang/Math/CubeRootTests.java test passed with the changes.

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Issue

• JDK-8353686: Optimize Math.cbrt for x86 64 bit platforms (Enhancement - P4)

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