Lando Norris’s early exit in Mexican Grand Prix qualifying acts as a costly lesson in self-discipline for a Formula 1 driver rightly disappointed with a “quite silly” mistake.Norris held his hands up after the error in Q1 that would ultimately leave the McLaren driver - who has finished on the podium at the last four races - in line to start from 19th on Sunday.He “messed up” into Turn 12, overdoing the entry and running wide onto the exit kerb entering the stadium section, which prompted a wild kick of the rear and an aborted lap. Norris is OUT of…