vmount: update control_data if already_active is true

control_data needs to be able to be set to nullptr in case if the input
is already active. Otherwise the output will think there's always new
requests and reset it's state.

src/drivers/vmount/vmount.cpp

@@ -337,7 +337,7 @@ static int vmount_thread_main(int argc, char *argv[])
 					continue;
 				}
 
-				if (control_data_to_check != nullptr) {
+				if (control_data_to_check != nullptr || already_active) {
 					control_data = control_data_to_check;
 					last_active = i;
 				}