core: documentation fixes

lib/private/encryption/keys/storage.php

@@ -114,7 +114,7 @@ class Storage implements \OCP\Encryption\Keys\IStorage {
 	 *
 	 * @param string $path path to file
 	 * @param string $keyId id of the key
-	 * @param mixed $key
+	 * @param boolean
 	 */
 	public function setFileKey($path, $keyId, $key) {
 		$keyDir = $this->getFileKeyDir($path);

lib/public/encryption/keys/istorage.php

@@ -69,7 +69,7 @@ interface IStorage {
 	 *
 	 * @param string $path path to file
 	 * @param string $keyId id of the key
-	 * @param mixed $key
+	 * @param boolean
 	 */
 	public function setFileKey($path, $keyId, $key);