LOS ANGELES (AP) — The music world lost a giant when heavy metal icon Ozzy Osbourne died last summer. So, what better way to kick off the famed Clive Davis pre-Grammys gala Saturday night than with a tribute to the prince of darkness? MGK (formerly known as Machine Gun Kelly) and country star Jelly Roll began the night of live music and tributes with Osbourne’s “I Don’t Wanna Stop” and “Mama, I’m Coming Home,” respectively, at the Beverly Hilton in Beverly Hills, Calif. “Rest in peace, Ozzy,”