libalias: Style cleanup

libalias is a convolut of various coding styles modified by a series
of different editors enforcing interesting convetions on spacing and
comments.

This patch is a baseline to start with a perfomance rework of
libalias. Upcoming patches should be focus on the code, not on the
style. That's why most annoying style errors should be fixed
beforehand.

Reviewed by: hselasky
Discussed by: emaste
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D30259