By Evan Bleier Barring a late commitment from Phil Mickelson to head to the links at Centurion Club outside London next week, Dustin Johnson will be the biggest name to risk his place on the PGA Tour for a spot on the LIV Golf Invitational Series. Johnson’s defection to the Saudi-backed LIV series was announced yesterday and the repercussions came quickly as his longtime sponsor Royal Bank of Canada dropped the 37-year-old like a bad habit. Graeme McDowell, the winner of the 2010 U.S. Open, was also dropped by the Canadian banking giant. McDowell and Johnson are not the only golfers to lose lu…