allow all-day events that span over multiple days, fixes #3872

Closes #3872

Merge request studip/studip!2727

app/controllers/calendar/date.php

@@ -386,7 +386,6 @@ class Calendar_DateController extends AuthenticatedController
             if (Request::get('all_day') === '1') {
                 $this->all_day_event = true;
                 $begin->setTime(0,0,0);
-                $end = clone $begin;
                 $end->setTime(23,59,59);
             }
             $this->date->begin = $begin->getTimestamp();

app/views/calendar/date/_add_edit_form.php

@@ -64,8 +64,7 @@
             </label>
         </div>
         <label>
-            <input type="checkbox" name="all_day" value="1" <?= $all_day_event ? 'checked' : '' ?>
-                   data-deactivates=".new-calendar-date-form input[name='end']">
+            <input type="checkbox" name="all_day" value="1" <?= $all_day_event ? 'checked' : '' ?>>
             <?= _('Ganztägiger Termin') ?>
         </label>
         <label>