dm crypt: replaced #if defined with IS_ENABLED

IS_ENABLED(CONFIG_ENCRYPTED_KEYS) is true whether the option is built-in
or a module, so use it instead of #if defined checking for each
separately.

The other #if was to avoid a static function defined, but unused
warning. As we now always build the callsite when the function
is defined, we can remove that first #if guard.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Acked-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

drivers/md/dm-crypt.c

@@ -2436,7 +2436,6 @@ static int set_key_user(struct crypt_config *cc, struct key *key)
 	return 0;
 }
 
-#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE)
 static int set_key_encrypted(struct crypt_config *cc, struct key *key)
 {
 	const struct encrypted_key_payload *ekp;
@@ -2452,7 +2451,6 @@ static int set_key_encrypted(struct crypt_config *cc, struct key *key)
 
 	return 0;
 }
-#endif /* CONFIG_ENCRYPTED_KEYS */
 
 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
 {
@@ -2482,11 +2480,10 @@ static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string
 	} else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) {
 		type = &key_type_user;
 		set_key = set_key_user;
-#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE)
-	} else if (!strncmp(key_string, "encrypted:", key_desc - key_string + 1)) {
+	} else if (IS_ENABLED(CONFIG_ENCRYPTED_KEYS) &&
+		   !strncmp(key_string, "encrypted:", key_desc - key_string + 1)) {
 		type = &key_type_encrypted;
 		set_key = set_key_encrypted;
-#endif
 	} else {
 		return -EINVAL;
 	}