fscrypt: remove unnecessary NULL check when allocating skcipher

crypto_alloc_skcipher() returns an ERR_PTR() on failure, not NULL.
Remove the unnecessary check for NULL.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

fs/crypto/keyinfo.c

@@ -318,8 +318,8 @@ int fscrypt_get_encryption_info(struct inode *inode)
 		goto out;
 	}
 	ctfm = crypto_alloc_skcipher(cipher_str, 0, 0);
-	if (!ctfm || IS_ERR(ctfm)) {
-		res = ctfm ? PTR_ERR(ctfm) : -ENOMEM;
+	if (IS_ERR(ctfm)) {
+		res = PTR_ERR(ctfm);
 		pr_debug("%s: error %d (inode %lu) allocating crypto tfm\n",
 			 __func__, res, inode->i_ino);
 		goto out;