xfrm: replace rwlock on xfrm_state_afinfo with rcu
xfrm: replace rwlock on xfrm_state_afinfo with rcu

Similar to commit 418a99ac6ad487dc9c42e6b0e85f941af56330f2
(Replace rwlock on xfrm_policy_afinfo with rcu), the rwlock
on xfrm_state_afinfo can be replaced by RCU too.

Cc: Steffen Klassert <66deb1d63f85161cc287ce2bac0c65cb5ae958a7@secunet.com>
Cc: Herbert Xu <ef65de1c7be0aa837fe7b25ba9a7739905af6a55@gondor.apana.org.au>
Cc: "David S. Miller" <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>
Signed-off-by: Cong Wang <b08afa93ec8eabe95bc97d12956ca699fa65834c@redhat.com>
Signed-off-by: Steffen Klassert <66deb1d63f85161cc287ce2bac0c65cb5ae958a7@secunet.com>

KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas