The rollover from your 401(k) to your IRA is not taxable.
If it was a direct rollover (aka as a trustee-to-trustee rollover) there is no real need to amend your return. However the IRS has a copy of your form 1099-R. But it is unlikely that they will contact you when they see that the code in box 7 of form 1099-R is for a direct rollover. That code should be G.