LOS ANGELES (Reuters) – Prosecutors on Tuesday asked a court to find R&B singer Chris Brown in violation of his probation because they say community service records stemming from his 2009 assault on girlfriend Rihanna contain "significant discrepancies." Brown is scheduled to appear at a hearing on Wednesday in Los Angeles, at which time a judge could decide to revoke the "Don't Wake Me Up" singer's probation. But Brown's attorney, Mark Geragos, told Reuters the allegations are "scurrilous, libelous and defamatory." "The prosecution has lost their collective minds," Geragos said. …