hwmon: (pmbus) Replace - with _ in device names before registration

The hwmon sysfs ABI requires that the `name` property doesn't include
any dashes. But when the pmbus code picks the name up from the device
tree it quite often does. Replace '-' with '_' before registering the
device.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Link: https://lore.kernel.org/r/20210317040231.21490-2-chris.packham@alliedtelesis.co.nz


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