[CRYPTO]: crypto_free_tfm() callers no longer need to check for NULL

Since the patch to add a NULL short-circuit to crypto_free_tfm() went in,
there's no longer any need for callers of that function to check for NULL.
This patch removes the redundant NULL checks and also a few similar checks
for NULL before calls to kfree() that I ran into while doing the
crypto_free_tfm bits.

I've succesfuly compile tested this patch, and a kernel with the patch 
applied boots and runs just fine.

When I posted the patch to LKML (and other lists/people on Cc) it drew the
following comments :

 J. Bruce Fields commented
  "I've no problem with the auth_gss or nfsv4 bits.--b."

 Sridhar Samudrala said
  "sctp change looks fine."

 Herbert Xu signed off on the patch.

So, I guess this is ready to be dropped into -mm and eventually mainline.

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sunrpc/auth_gss/gss_spkm3_mech.c b/net/sunrpc/auth_gss/gss_spkm3_mech.c
index dad0599..6c97d61 100644
--- a/net/sunrpc/auth_gss/gss_spkm3_mech.c
+++ b/net/sunrpc/auth_gss/gss_spkm3_mech.c
@@ -214,14 +214,10 @@
 gss_delete_sec_context_spkm3(void *internal_ctx) {
 	struct spkm3_ctx *sctx = internal_ctx;
 
-	if(sctx->derived_integ_key)
-		crypto_free_tfm(sctx->derived_integ_key);
-	if(sctx->derived_conf_key)
-		crypto_free_tfm(sctx->derived_conf_key);
-	if(sctx->share_key.data)
-		kfree(sctx->share_key.data);
-	if(sctx->mech_used.data)
-		kfree(sctx->mech_used.data);
+	crypto_free_tfm(sctx->derived_integ_key);
+	crypto_free_tfm(sctx->derived_conf_key);
+	kfree(sctx->share_key.data);
+	kfree(sctx->mech_used.data);
 	kfree(sctx);
 }