Corrected 2D relicts in 3D function comments (#12406)
Corrected 2D relicts in 3D function comments (#12406)

* Corrected 2D relicts in 3D function comments

Some argument descriptions referred to "two" values, which for 3D functions must be "three".

* Added missing "depth" comment in 3D function

keras-team/keras,keras-team/keras