Pandemonium broke out during the taping of Vibe magazine's award show last night, when a man was stabbed during the ceremony, sending stars fleeing from the mayhem in their limos. The violence broke out as rapper Dr. Dre rose to accept the Vibe Legend Award from presenters Quincy Jones and Snoop Dogg, a witness at the Santa Monica event told The Post. An unidentified man sitting with Death Row Records chief Marion "Suge" Knight lunged toward Dr. Dre with a knife — but members of rapper 50 Cent's entourage intervened, the witness said. [snip] The witness said that the...