Convert fallthrough comment to pseudo-keyword in Standard extension

Author: Girgias

ext/standard/array.c

@@ -770,7 +770,7 @@ PHP_FUNCTION(count)
 				return;
 			}
 		}
-		/* fallthrough */
+		fallthrough;
 		default:
 			zend_argument_type_error(1, "must be of type Countable|array, %s given", zend_zval_type_name(array));
 			RETURN_THROWS();

ext/standard/exec.c

@@ -358,7 +358,7 @@ PHPAPI zend_string *php_escape_shell_cmd(const char *str)
 #else
 				ZSTR_VAL(cmd)[y++] = '\\';
 #endif
-				/* fall-through */
+				fallthrough;
 			default:
 				ZSTR_VAL(cmd)[y++] = str[x];
 
@@ -432,7 +432,7 @@ PHPAPI zend_string *php_escape_shell_arg(const char *str)
 			ZSTR_VAL(cmd)[y++] = '\\';
 			ZSTR_VAL(cmd)[y++] = '\'';
 #endif
-			/* fall-through */
+			fallthrough;
 		default:
 			ZSTR_VAL(cmd)[y++] = str[x];
 		}

ext/standard/math.c

@@ -773,7 +773,7 @@ PHPAPI void _php_math_basetozval(zend_string *str, int base, zval *ret)
 				fnum = (double)num;
 				mode = 1;
 			}
-			/* fall-through */
+			fallthrough;
 		case 1: /* Float */
 			fnum = fnum * base + c;
 		}