ext/pdo_firebird: Fix label follow by declaration

A label should be followed by a statement and not a declaration, else old gcc gives the following error: a label can only be part of a statement and a declaration is not a statement

To fix this we add a ; after the case label before the declaration.

Author: shivammathur

ext/pdo_firebird/firebird_statement.c

@@ -886,7 +886,7 @@ static int pdo_firebird_stmt_set_attribute(pdo_stmt_t *stmt, zend_long attr, zva
 	switch (attr) {
 		default:
 			return 0;
-		case PDO_ATTR_CURSOR_NAME:
+		case PDO_ATTR_CURSOR_NAME: ;
 			zend_string *str_val = zval_try_get_string(val);
 			if (str_val == NULL) {
 				return 0;