Fix [-Wimplicit-fallthrough] warnings in Phar extension

Author: Girgias

ext/phar/phar_object.c

@@ -1485,7 +1485,7 @@ static int phar_build(zend_object_iterator *iter, void *puser) /* {{{ */
 						goto phar_spl_fileinfo;
 				}
 			}
-			/* fall-through */
+			fallthrough;
 		default:
 			zend_throw_exception_ex(spl_ce_UnexpectedValueException, 0, "Iterator %s returned an invalid value (must return a string)", ZSTR_VAL(ce->name));
 			return ZEND_HASH_APPLY_STOP;

ext/phar/util.c

@@ -1892,6 +1892,7 @@ int phar_create_signature(phar_archive_data *phar, php_stream *fp, char **signat
 		break;
 		default:
 			phar->sig_flags = PHAR_SIG_SHA1;
+			fallthrough;
 		case PHAR_SIG_SHA1: {
 			unsigned char digest[20];
 			PHP_SHA1_CTX  context;