Apply FreeBSD rev 1.6:

Apply FreeBSD rev 1.6:
  date: 2003-06-29 16:58:38 -0700;  author: sam;  state: Exp;  lines: +13 -2;
  plug xform memory leaks:

  o add missing zeroize op when deleting an SA
  o don't re-initialize an xform for an SA that already has one

  Submitted by:   Doug Ambrisko <ambrisko@verniernetworks.com>