LOS ANGELES – A Sylmar man was charged today in a federal grand jury indictment alleging that he deliberately set Hollywood’s Pizzeria Mozza restaurant on fire during the civil disturbances that struck the city in late May.         Mario Ernesto Alvarado, 42, is charged with one count of arson. His arraignment is scheduled for August 10 in United States District Court. Alvarado was arrested on a federal criminal complaint in this case on July 16. He is free on $25,000 bond.         During the civil disturbances that occurred in Los Angeles on May 30, Alvarado allegedly walked into a commercial...