Lusty leprechaun Colin Farrell is finally out of rehab for his addiction to prescription drugs. The irrepresible Irishman, who suffered from a boozy bloat on the South Beach set of “Miami Vice” last year, cruised up to the Hard Rock Hotel & Casino in Las Vegas on a Harley-Davidson and had lunch with four friends at Lucky ‘s, the hotel ‘s diner. A spy swears Farrell only had sodas and a pack of cigarettes for lunch and was later overheard asking hotel staff for “directions to the Grand Canyon.”