Cleanup: remove unneeded check in uiTemplateConstraintHeader

Following rB7a0a60dde8b4, checking for temporary IK constraints in
uiTemplateConstraintHeader is not needed anymore (since the whole panel
will now be skipped earlier for those).

Differential Revision: https://developer.blender.org/D8902

source/blender/editors/interface/interface_templates.c

@@ -2694,14 +2694,6 @@ void uiTemplateConstraintHeader(uiLayout *layout, PointerRNA *ptr)
 
   UI_block_lock_set(uiLayoutGetBlock(layout), (ob && ID_IS_LINKED(ob)), ERROR_LIBDATA_MESSAGE);
 
-  /* hrms, the temporal constraint should not draw! */
-  if (con->type == CONSTRAINT_TYPE_KINEMATIC) {
-    bKinematicConstraint *data = con->data;
-    if (data->flag & CONSTRAINT_IK_TEMP) {
-      return;
-    }
-  }
-
   draw_constraint_header(layout, ob, con);
 }