By Tzvi Machlin NBA legend Magic Johnson has spared no expense in adding several sports franchises to his portfolio. But there’s one NFL team that he would like to add. According to Semafor, Johnson is interested in buying a stake in the Las Vegas Raiders. To that end, the NBA legend is already in talks with investors to obtain a minority share in the franchise from principal owner Mark Davis. Per the report, the Raiders have previously received bids on the club but turned them down. However, their most recent bid reportedly put the team valuation at a whopping $6.3 billion – which would make …