950q i2c fixes

This weekend continued to work on various outstanding 950q analog bugs. Isolated one of the more annoying problems related to i2c enumeration returning false positives, and checked in a fix (removing the really nasty hack).

The list of things outstanding for the merge is getting shorter:

• More testing
• Robert's case of "choppy video"
• Conversion to new video subdev framework
• Possible issue with colorspace one user reported with mplayer (so far unreproducible)

In addition, I'm still looking to do the following at some point after the merge

• VBI support
• Better power management when idle