crypto: skcipher - remove crypto_skcipher::keysize

Due to the removal of the blkcipher and ablkcipher algorithm types,
crypto_skcipher::keysize is now redundant since it always equals
crypto_skcipher_alg(tfm)->max_keysize.

Remove it and update crypto_skcipher_default_keysize() accordingly.

Also rename crypto_skcipher_default_keysize() to
crypto_skcipher_max_keysize() to clarify that it specifically returns
the maximum key size, not some unspecified "default".

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

fs/ecryptfs/crypto.c

@@ -1586,7 +1586,7 @@ ecryptfs_process_key_cipher(struct crypto_skcipher **key_tfm,
 	}
 	crypto_skcipher_set_flags(*key_tfm, CRYPTO_TFM_REQ_FORBID_WEAK_KEYS);
 	if (*key_size == 0)
-		*key_size = crypto_skcipher_default_keysize(*key_tfm);
+		*key_size = crypto_skcipher_max_keysize(*key_tfm);
 	get_random_bytes(dummy_key, *key_size);
 	rc = crypto_skcipher_setkey(*key_tfm, dummy_key, *key_size);
 	if (rc) {