media: staging: atomisp: i2c: Disable non-preview configurations

These sensor drivers have use case specific mode lists. This is currently
not used nor there is a standard API for selecting the mode list. Disable
configurations for non-preview modes until configuration selection is
improved so that all the configurations are always usable.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
[hans.verkuil@cisco.com: clarify that this functionality it currently unused]
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>