Enable sysops to update their own BBS details

app/Http/Controllers/SystemController.php

@@ -244,7 +244,7 @@ class SystemController extends Controller
 	public function add_session(Request $request,System $o)
 	{
 		// @todo This should be admin of the zone
-		$this->authorize('admin',$o);
+		$this->authorize('update',$o);
 		session()->flash('accordion','session');
 
 		$validate = $request->validate([