More TV card support

Sascha Wildner’s added the cxm(4) driver, which supports Hauppauge PVR-250/350 video capture cards.  Hasso Tepper kindly donated the hardware for testing.

I’ll note here that I have a Hauppauge TV card (848 chipset, I think) that’s possibly the oldest continuously functioning computer equipment I own; I’ve been using it for close to a decade without a single problem.  I have nothing else that has reached the benchmark.