New defgroup pixel-scroll-precision

New defgroup pixel-scroll-precision

* lisp/pixel-scroll.el (pixel-scroll-precision): New defgroup.
(pixel-scroll-precision-use-momentum)
(pixel-scroll-precision-momentum-tick)
(pixel-scroll-precision-momentum-seconds)
(pixel-scroll-precision-momentum-min-velocity)
(pixel-scroll-precision-initial-velocity-factor)
(pixel-scroll-precision-large-scroll-height)
(pixel-scroll-precision-interpolation-total-time)
(pixel-scroll-precision-interpolation-factor)
(pixel-scroll-precision-interpolation-between-scroll)
(pixel-scroll-precision-interpolate-page)
(pixel-scroll-precision-interpolate-mice): Move to above new
defgroup.  (Bug#57970)
* lisp/mouse.el (mouse): Remove stale comment.