[ros-kernel] functions for i81x drivers

[Waldo Alvarez]

I was inspecting my intel 815 driver for Win2k and all functions it 
imports seems to be implemented in ReactOS except this ones in 
videoprt.sys

VideoPortEnumerateChildren
VideoPortGetAssociatedDeviceExtension
VideoPortGetStallExecution
VideoPortSyncronizeExecution

I presume that if they are implemented, ROS will be able to support the
whole i81x family since they all use the same driver. A little luck is 
needed too :).

I promise to test ROS in real hardware using the driver and give feedback 
in here.

Best Regards
Waldo Alvarez