orient: Commit 79c0966 had an un-noticed effect on the behaviour of M19

reported in #3389
Prior to the change M19 would turn spindle-on to "off". After it remains on
with speed=0. This commot adds an explicit spindle-off to the M19 behaviour.

Author: andypugh

src/emc/motion/command.c

@@ -1693,6 +1693,11 @@ void emcmotCommandHandler_locked(void *arg, long servo_period)
 	        // so far like spindle stop, except opening brake
 	        emcmotStatus->spindle_status[n].brake = 0; // open brake
 
+            // https://github.com/LinuxCNC/linuxcnc/issues/3389
+            emcmotStatus->spindle_status[n].state = 0;
+            *(emcmot_hal_data->spindle[n].spindle_on) = 0;
+            // https://github.com/LinuxCNC/linuxcnc/issues/3389
+
 	        *(emcmot_hal_data->spindle[n].spindle_orient_angle) = emcmotCommand->orientation;
 	        *(emcmot_hal_data->spindle[n].spindle_orient_mode) = emcmotCommand->mode;
 	        *(emcmot_hal_data->spindle[n].spindle_locked) = 0;

src/emc/motion/motion.h

@@ -255,7 +255,7 @@ extern "C" {
     int probe_home_err_inhibit;  // setting to inhibit probe tripped while homeing error.
     EmcPose tool_offset;        /* TLO */
     double  orientation;    /* angle for spindle orient */
-    int state; /*spindle state*/
+    int state; /*spindle state  seems to just be 0 for off and 1 for on andypugh 2025-04-03*/
     char    direction;      /* CANON_DIRECTION flag for spindle orient */
     double  timeout;        /* of wait for spindle orient to complete */
     unsigned char wait_for_spindle_at_speed; // EMCMOT_SPINDLE_ON now carries this, for next feed move