The Pittsburgh Steelers are signing punter Corliss Waitman after Cameron Johnston suffered a season-ending knee injury on Sunday. Waitman’s agent, Alexa Stabler, shared the news with Tom Pelissero of the NFL Network, and this will be Waitman’s third stint with Pittsburgh. Waitman, 29, first signed with the Steelers in 2020 as an undrafted free agent from South Alabama. He was waived before the 2020 season began but was re-signed to the team’s practice squad. Waitman was waived by the Raiders again in May 2021 before signing with the Las Vegas Raiders in July. He was waived by the Raiders in Au…