PAX MPROTECT: mprotect(2) hardening
github-issue: #37

Add a small mprotect(2) hardening feature that prevents marking a
mapping as executable if it wasn't created executable. Inspired by the
EuroBSDCon 2014 presentation by Philip Guenther.
HBSD: fixed sysinit information messagese, and reorder variables

Signed-off-by: Oliver Pinter <oliver.pntr@gmail.com>