Auto-initialize PAL when functions are called before et_pal_init()

[rascani]

Summary

Replace the debug-only assertion behavior with automatic initialization. When et_pal_current_ticks() or et_pal_emit_log_message() are called before et_pal_init(), they now call et_pal_init() automatically instead of aborting in debug builds or producing undefined behavior in release.

Uses std::call_once with a function-local static flag for thread-safe one-time initialization.

Rename executor_pal_death_test to executor_pal_autoinit_test since we now test auto-initialization behavior rather than death on missing init.

[pytorch-bot]

🔗 Helpful Links

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❌ 5 New Failures, 3 Cancelled Jobs

As of commit d04ac21 with merge base 505c5c9 ():

NEW FAILURES - The following jobs have failed:

• pull / test-binary-size-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 43b21722ffacbd70472792616822ef186295d791c044eb9928c4669f786390a5 /exec failed with exit code 1
• pull / test-openvino-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 1e12c20b689f28e55b92220845ff7f46014163028af09be3f13fd1ba9b6079a8 /exec failed with exit code 1
• pull / test-samsung-models-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 394ecda57855cfb0d46998d3c7c419fa3746454dcab70e7aa3a0aa2247dc72d2 /exec failed with exit code 1
• pull / test-samsung-quantmodels-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 6722df4bab26f55f434a588f2a9a15877ad54ff041cee25d45f33c4a813418b8 /exec failed with exit code 1
• pull / unittest-nxp-neutron / linux-job (gh)
  RuntimeError: Command docker exec -t ef065f9b4d4eabba1048f6d9d15ae43ed9aa9c25a219c4aa20ec69c13d82658a /exec failed with exit code 1

CANCELLED JOBS - The following jobs were cancelled. Please retry:

• pull / test-models-linux (ic4, portable, linux.4xlarge.memory) / linux-job (gh)
• pull / test-qnn-models-linux / linux-job (gh)
  ##[error]The operation was canceled.
• Test CUDA Builds / test-models-cuda (mv2) / linux-job (gh)
  ##[error]The operation was canceled.

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[meta-codesync]

@rascani has imported this pull request. If you are a Meta employee, you can view this in D93765646.