hwmon: (ina2xx) fix sysfs shunt resistor read access

[ Upstream commit 3ad867001c91657c46dcf6656d52eb6080286fd5 ]

fix the sysfs shunt resistor read access: return the shunt resistor
value, not the calibration register contents.

update email address

Signed-off-by: Lothar Felten <lothar.felten@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>