ds2760_battery: Fix indexing of the 4 active full EEPROM registers

Fix indexing of the 4 active full EEPROM registers. The indexing was out by 1, accessing the EEPROM registers at 0x23 to 0x26 instead of 0x22 to 0x25.

Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>