nvpair: chase FreeBSD xdrproc_t definition

[brooksdavis]

As of FreeBSD 16, xdrproc_t will take exactly two arguments in both kernel and userspace in line with the Linux kernel.

Signed off by: Brooks Davis brooks@capabilitieslimited.co.uk

Motivation and Context

See the FreeBSD commit message for the logic behind this change https://cgit.freebsd.org/src/commit/?id=ac5a19ec6989675c8ec6c3ca245dba243d1a6416

Description

When building FreeBSD 16, always use the 2 direct argument prototype for xdrproc_t. I've committed a variant of this to FreeBSD.

How Has This Been Tested?

It builds and the prototype doesn't change the ABI on currently supported platforms (which is why the divergent declarations work at all).

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Performance enhancement (non-breaking change which improves efficiency)
• Code cleanup (non-breaking change which makes code smaller or more readable)
• Quality assurance (non-breaking change which makes the code more robust against bugs)
• Breaking change (fix or feature that would cause existing functionality to change)
• Library ABI change (libzfs, libzfs_core, libnvpair, libuutil and libzfsbootenv)
• Documentation (a change to man pages or other documentation)

Checklist:

• My code follows the OpenZFS code style requirements.
• I have updated the documentation accordingly.
• I have read the contributing document.
• I have added tests to cover my changes.
• I have run the ZFS Test Suite with this change applied.
• All commit messages are properly formatted and contain Signed-off-by.