By Thiam Ndiaga and Anne Mimault OUAGADOUGOU (Reuters) – Thousands of mourners gathered in Burkina Faso’s capital on Saturday for the funeral of 27 soldiers killed in an ambush last month that triggered the country’s second coup this year led by a military unit fed up with rampant insecurity. The coffins were wrapped in the Burkina Faso flag and sided by portraits of the soldiers who were killed on Sept. 26 while escorting a convoy that was delivering supplies to a northern town besieged by Islamist insurgents. “People are saddened and sickened by the situation we are experiencing. It really h…