ds2760_battery: Fix rated capacity of the hx4700 1800mAh battery

Fix rated capacity of the HP iPAQ hx4700 3.7V 1800mAh (359113-001) battery. For this battery the value of the rated capacity EEPROM register at 0x32 is 7; thus rated_capacities[7] = 1800.

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