Since this results in no changes to any dollar amounts, the only part of Form 1040-X that would be relevant is the explanation section. It seems simpler to just retain your information and provide explanation if the IRS ever questions the rollover, which seems unlikely since the copy of the Form 1099-R sent to the IRS by the plan shows this as a nontaxable rollover and the Form 5498 provided to the IRS by the IRA custodian will show receipt of the rollover.
