HBSD: paxify ptrace hardening

github-issue: #60 #62
Signed-off-by: Oliver Pinter <oliver.pinter@hardenedbsd.org>
HBSD: make PTRACE_HARDENING_GRP compile time configurable

github-issue: #60 #62
Signed-off-by: Oliver Pinter <oliver.pntr@gmail.com>