Mixing view interpolation with finishing smooth-view caused arguments
to be passed in that only made sense for one of these cases.
This also makes the intention of the callers clearer.
- view3d_smoothview_apply_with_interp
- view3d_smoothview_apply_and_finish
- view3d_smoothview_apply_from_timer
Also rename 'step' to 'factor` and use `interpf` for blending values.
a26b1a299f