HBSD NOEXEC: use the new API in sys_obreak

github-issue: #37
Signed-off-by: Oliver Pinter <oliver.pinter@hardenedbsd.org>
HBSD NOEXEC: get ride of PAX_PAGEEXEC and PAX_MPROTECT knob, and use PAX_NOEXEC instead

github-issue: #37
Signed-off-by: Oliver Pinter <oliver.pinter@hardenedbsd.org>
HBSD NOEXEC: unify some code

github-issue: #37
Signed-off-by: Oliver Pinter <oliver.pinter@hardenedbsd.org>
HBSD NOEXEC: fix build, which breaked in dd5248b04ef7f79646d8b0605410e5d0a3eb468c

github-issue: #37
Signed-off-by: Oliver Pinter <oliver.pntr@gmail.com>