jogging: ignore feedoverride

Prior behavior: feedoverride affects:
   1) wheel jogging   (axis.N.jog-*)
   2) halui jogging   (halui.jog*)
   3) axis ui jogging

New behavior: feedoverride ignored for motion_state==EMCMOT_MOTION_FREE.

Notes:
  1) for wheel jogging, the jog rate can be managed
     with axis.N.jog-scale, axis.N.jog-counts
     (ref: man motion)
  2) for halui jogging, the rate can be managed with
     halui.jog-speed (for plus/minus jogging)
     (ref: man halui)
  3) the axis ui provides individual sliders for both
     linear and angular jog rates

Signed-off-by: Dewey Garrett <dgarrett@panix.com>