By Sabrina Valle HOUSTON (Reuters) -Exxon Mobil Corp on Monday disclosed a sweeping restructuring of its global operations that will combine its refining and chemicals businesses into one, and put its energy transition business on the same footing as its other operations. The broad restructuring marks its latest cost-cutting effort after activist investors seeking to boost returns and address the energy transition won three seats last spring on its board. Exxon vowed to cut $6 billion from operating costs by next year after suffering a historic $22.4 billion loss in 2020. The changes were firs…