After a little absence, here's a patch to bring the Philips Webcam driver up
to version 8.9 (skipping 8.8 which has been available as a download on my
website for a while).

This patch is against 2.5.49, and includes some of the following:
* New USB IDs for Logitech and Visionite webcams.
* Better URB link/unlink sequence when opening/closing device
  and switching resolutions.
* Adding probe for CCD/CMOS sensor type.
* Removed remnants of YUV420 palette stuff.

Also updated the description in 'Kconfig'.