staging: iio: tsl2583: move from a global to a per device lux table

The driver contains a global lux table that can be updated via sysfs.
Change this to a per device lux table so that multiple devices can be
hooked up to the same system with different lux tables.

There are 10 entries, plus 1 for the termination segment, set aside for
the entries in the lux table. When updating the lux table via sysfs,
only 9 entries, plus the terminator, could be added. This changes
the code to allow for the 10 entries, plus the terminator.

Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>