By Mathieu Rosemain PARIS (Reuters) – Shares in IT consulting firm Atos tumbled 10% on Monday following a news report signalling that its investor day this week may offer little progress on the potential sale of part of its activities. The French firm, deemed strategic by the government for its high-tech assets such the manufacture of supercomputers, has yet to recover from a series of setbacks that wiped out close to two-thirds of its share price and led to the reshuffling of its top management. French news website BFM Business reported earlier on Monday that Atos’ major announcement at its i…