By Dave Sherwood HAVANA (Reuters) – A U.S. government delegation met Cuban officials in Havana on Wednesday to discuss Washington’s concerns about irregular migration from the island, marking the highest-level known U.S. visit since the historic rapprochement under former President Barack Obama. U.S. Assistant Secretary of State for Consular Affairs Rena Bitter and U.S. Citizenship and Immigration Services Director Ur Jaddou held talks with Cuban Vice Foreign Minister Carlos Fernandez de Cossio at the embassy in Havana, and detailed plans to resume “full immigrant visa processing” on Jan. 4. T…