hwmon: (it87) Use voltage scaling macro where appropriate

Apply scaling macro to match the labels for internal voltage sensors.

Signed-off-by: Frank Crawford <frank@crawford.emu.id.au>
Link: https://lore.kernel.org/r/20230318080543.1226700-3-frank@crawford.emu.id.au


Signed-off-by: Guenter Roeck <linux@roeck-us.net>