Oct 11 (Reuters) - The six biggest U.S. banks are expected to have set aside nearly $5 billion in the third quarter to cover future loan losses, Wall Street analysts said, as lenders brace for a potential global recession. Profits at big banks got a boost last year as they released funds reserved for potential COVID losses. In the third quarter of last year, they released about $4 billion of loan provisions, according to data from Refinitiv. But with growing fears of a recession as the U.S. Federal Reserve hikes interest rates aggressively to tamp down inflation, reserves in the...