By the Rangers locking up home-ice advantage for the first round of the playoffs with Thursday night’s 2-1 squeaker of a win over the Sabres at the Garden, their lineup for Saturday’s regular-season finale in Montreal is up in the air. First on their possible rest list would be goalie Henrik Lundqvist, who has a sordid track record in the Bell Center and has started five games in a row, as well as 19 of the last 21 going back to March 1. Backup Cam Talbot last played on March 30 in Edmonton. “I’ve already made up my mind on who I’m going to play depending on how important the game is,” said coach Alain Vigneault before he knew the Flyers lost, 4-2, to the Lightning, thus locking up the Rangers’ home ice. “I haven’t told my goalie yet, so I’m going to wait until I see him first.” The Rangers have played the past four games without No. 1 defenseman Ryan McDonagh, suffering from a left-shoulder injury. Vigneault had been debating the merits of playing him before the postseason, and the plan was for McDonagh to skate by himself on Friday while the team doesn’t practice and flies to Montreal in the afternoon.