twl6030 battery: add lookup table for initial capacity estimation

Add a lookup table for estimating battery capacity at bootup
using the battery voltage measrued at that time.

The table was constructed using actual measured values for Blaze
Tablets. The values don't correspond to the arbitrary values currently
used in the driver.

This table is something that a board file should pass to the
driver. This will be introduced in a later patch - for now, we
keep the values in the driver just like the current design.

Change-Id: I78b35b68c7a41b67d67925dae8015405efb44b0d
Signed-off-by: Sivakumar Pothireddy <sivakumar.pothireddy@ti.com>
Signed-off-by: Anand Gadiyar <gadiyar@ti.com>