When trying to spddelete individual entries using setkey, spddelete always 
fails.  The culprit is in net/af_key.c; spdadd sets the family field of the 
selector when creating an entry, but spddelete doesn't when building a 
selector to match for xfrm_policy_bysel.  Trivial fix is to have spddelete 
set the family field in the selector in same way spdadd does.