By Elvira Pollina MILAN (Reuters) -The board of Telecom Italia (TIM) will on Tuesday start examining a proposal from CVC for a stake in its enterprise services business and its directors will be also be briefed on discussions with KKR over a rival approach. CVC has put a value of 6 billion euros ($6.6 billion) including debt on what would be a newly created TIM enterprise services business, a source said on Tuesday. The interest from CVC comes as TIM Chief Executive Pietro Labriola presses ahead with a plan to split TIM’s service business from its network operations as part of a broader strate…