[Build] Fix for DeepEP manylinux pidfd sycall usage

[tlrmchlsmth]

Fix the release pipeline.

I think this comment explains the issue pretty well

    # DeepEPv2 requires Linux 5.6+ at runtime for pidfd_getfd (pidfd_open was
    # added in Linux 5.3), but manylinux headers predate both definitions.
    # DeepEP is built as a separate wheel for the vLLM container image and is
    # not included in the vLLM wheel, so this does not change its manylinux ABI.

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