power_supply: max77693: Make min/max charging current limit configurable
Adds two new properties, "maxim,min-charge-microamps" and "maxim,max-charge-microamps", that control the minimum/maximum current allowed for charging. By default, use the default min/max values for 0.5A (500000 uA).
Also make the Galaxy Tab 3 8.0 use those values.
(Note that this does not update dt-bindings to include the new values; if I should add that too, let me know.)