Fix CTASSERT issue in a more clean way

• Replace all CTASSERT macro instances with static_assert's.
• Remove the WRAPPED_CTASSERT macro; it's now an unnecessary obfuscation.
• Localize all static_assert's to the structures being tested.
• Sort some headers per-style(9).

Approved by: re (hrs)
Differential Revision: https://reviews.freebsd.org/D7130
MFC after: 1 week
X-MFC with: r302364
Reviewed by: ed, grehan (maintainer)
Submitted by: ed
Sponsored by: EMC / Isilon Storage Division