[nodejs-once/f18] (3 commits) ...restrict to compatible arches

[T.C. Hollingsworth]

Summary of changes:

  9623b34... add macro for EPEL6 dependency generation (*)
  8369cdc... invoke EPEL dependency generator macro conditionally to mak (*)
  e5367b3... restrict to compatible arches (*)

(*) This commit already existed in another branch; no separate mail sent