[Support/ELF] - Add OpenBSD PT_OPENBSD_RANDOMIZE, PT_OPENBSD_WXNEEDED constants.
[Support/ELF] - Add OpenBSD PT_OPENBSD_RANDOMIZE, PT_OPENBSD_WXNEEDED constants.

Docs for reference:
http://man.openbsd.org/OpenBSD-current/man5/elf.5
https://github.com/openbsd/src/commit/2a5a8fc7e30928c2cff57cfe5fb491c90d8478ad

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@283872 91177308-0d34-0410-b5e6-96231b3b80d8

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