hwmon: (ina2xx) Add support for INA220 and INA230

INA220 is register compatible to INA219, and INA230 is register compatible to
INA226, so all we need to do is to add name aliases for those two chips.

Cc: Lothar Felten <l-felten@ti.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Jean Delvare <khali@linux-fr.org>