PROF-12102: The stacktraces are not obeying the stackdepth limit

[rkennke]

What does this PR do?:
This change fixes the profiler such that it only reports a maximum of frames as specified by -Ddd.profiling.stackdepth or the jstackdepth agent argument. Previously this limited only the number of Java frames, and still report an arbitrary number of native frames, which makes the usefulness of that argument questionable.

Motivation:
The profiler should obey the requested maximum number of stackframes, this improves usefulness and usability. In addition to that, it also saves storage in the generated JFR and in-memory, because we don't need to allocate buffers for so many frames.

Additional Notes:
Notice that when no stackdepth is specified, a default stackdepth of 2048 is assumed. In getNativeFrames(), I keep limiting this to MAX_NATIVE_FRAMES to avoid suprises.

How to test the change?:
It's not feasible to make an automated test for this, this would require very significant upfront work in the JVM. I ran existing tests and found no regressions, and I verified manually that the fix works, by running the CPU profiler with a workload and the jstackdepth argument, and verified in JMC that the stack-depth gets correctly limited.

For Datadog employees:

• If this PR touches code that signs or publishes builds or packages, or handles
  credentials of any kind, I've requested a review from @DataDog/security-design-and-guidance.
• This PR doesn't touch any of that.
• JIRA: PROF-12102

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