This patch removes an annoying problem in xfrm_user.  As it is every
time an SA is added it probes every known algorithm in the universe.
Now if they all existed it would be OK.  However, for the ones which
don't actually exist this causes multiple /sbin/modprobe processes to
be spawned which slows the system down when you're adding hundreds of
SAs.

Since we know the type of algorithm required when we're adding a new
SA, we can get away with only probing the selected algorithms.  This
is what the following patch does for xfrm_user.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: James Morris <jmorris@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>