Merge branch 'libbpf/xsk cleanups'

Björn Töpel says:

====================

This series removes a header dependency from xsk.h, and moves
libbpf_util.h into xsk.h.

More details in each commit!

Thank you,
Björn
====================

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>