I referred some websites and finally found following command,
SELECT 'EXEC sp_rename '+ ''''+s.NAME+ '.' + p.NAME+''','''+s.NAME+ '.' +'your_suffix'+p.NAME+'''' FROM SYS.PROCEDURES p ,SYS.SCHEMAS s WHERE p.schema_id = s.schema_id
Warning: Executing this command is dangerous because it may rename system stored procedures too. To avoid such disaster, don't forget to include WHERE condition.
By AlpesH Shah