A British businessman and his Greek associate have been found guilty of brokering illegal weapons sales worth tens of millions of pounds to warlords across Africa and the Middle East.David Greenhalgh, 68, from Croydon in south London, and Christos Farmakis, 48, a Greek citizen, were found guilty at Southwark Crown Court on Thursday of facilitating black market arms deals to Libya, Sudan and South Sudan.The illicit operation ran from 2009 to 2016…