Fix T73740: Auto-key "Only Available" de-selects f-curves

This was especially bad with "Only Selected Curve Keyframes",
effectively making f-curves un-editable on each insertion.

source/blender/editors/animation/keyframing.c

@@ -3016,8 +3016,6 @@ bool ED_autokeyframe_property(
       ToolSettings *ts = scene->toolsettings;
       short flag = ANIM_get_keyframing_flags(scene, 1);
 
-      fcu->flag &= ~FCURVE_SELECTED;
-
       /* Note: We use rnaindex instead of fcu->array_index,
        *       because a button may control all items of an array at once.
        *       E.g., color wheels (see T42567). */

source/blender/editors/transform/transform_convert.c

@@ -1417,7 +1417,6 @@ void autokeyframe_object(bContext *C, Scene *scene, ViewLayer *view_layer, Objec
       if (adt && adt->action) {
         ListBase nla_cache = {NULL, NULL};
         for (fcu = adt->action->curves.first; fcu; fcu = fcu->next) {
-          fcu->flag &= ~FCURVE_SELECTED;
           insert_keyframe(bmain,
                           reports,
                           id,