Fix small memory leak in ecpglib ecpg_update_declare_statement() is called the

second time.

Author: "Zhang, Jie" <zhangjie2@cn.fujitsu.com>

src/interfaces/ecpg/ecpglib/prepare.c

@@ -754,8 +754,12 @@ ecpg_update_declare_statement(const char *declared_name, const char *cursor_name
 	/* Find the declared node by declared name */
 	p = ecpg_find_declared_statement(declared_name);
 	if (p)
+	{
+		if (p->cursor_name)
+			ecpg_free(p->cursor_name);
 		p->cursor_name = ecpg_strdup(cursor_name, lineno);
 	}
+}
 
 /*
  * Find and return the connection name referred by the declared name