Support for MSP3410D / MSP3415D Stereo/Mono audio using the audio format

Support for MSP3410D / MSP3415D Stereo/Mono audio using the audio format
Auto Detection Mode. This leaves MSP3400C owners still unsupported.
Thanks to Gerd Knorr <kraxel@cs.tu-berlin.de> for providing some early
assistance and sample code in the linux bttv driver.
Nicolas Souchu <nsouch@freebsd.org> ported the msp_read/write/reset
functions to smbus/iicbus.

METEOR_INPUT_DEV2 now selects a composite camera on the SVIDEO port.
For true SVIDEO, use METEOR_INPUT_DEV_SVIDEO.
If you get a monochrome image from the SVIDEO port, you have
seleted the wrong input type.

Tested by:      Johan Larsson<gozer@ludd.luth.se>