snd_hda.4: Improve HARDWARE for HW Relnotes

Rewrite the HARDWARE section to improve the hardware release notes.
Move the section to achieve the structure in mdoc(7). Tag SPDX.

MFC after: 3 days
Discussed with: mav
Reviewed by: christos
Approved by: mhorne (mentor, implicit)
Differential Revision: https://reviews.freebsd.org/D48503

(cherry picked from commit 7b34c48e036e209321174100ab9d7fef19b4932a)