[parrot/parrot] d220be: [GH #846] Harmonize generic/cpu_type.c: "unknown"

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/parrot/parrot
  Commit: d220be78f933206d29f5d687a356681eeb0fbbb1
      https://github.com/parrot/parrot/commit/d220be78f933206d29f5d687a356681eeb0fbbb1
  Author: Reini Urban <rurban at cpanel.net>
  Date:   2012-09-27 (Thu, 27 Sep 2012)

  Changed paths:
    M ChangeLog
    M src/platform/generic/cpu_type.c

  Log Message:
  -----------
  [GH #846] Harmonize generic/cpu_type.c: "unknown"

Harmonize with win32 version:
Return "unknown" not ""
Add PARROT_CANNOT_RETURN_NULL
Fix description