This is a couple of clean-ups stemming from the xfrm_output change.

I should've removed the inet_ecn.h inclusions in that change as the
ECN code has been moved to xfrm[46]_output.c.  This patch does exactly
that.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@redhat.com>