hwmon: (pmbus) Introduce and use write_byte_data callback

Some of the pmbus core functions uses pmbus_write_byte_data, which does
not support driver callbacks for chip specific write operations. This
could potentially influence some specific regulator chips that for
example need a time delay before each data access.

Lets add support for driver callback with _pmbus_write_byte_data.

Signed-off-by: Mårten Lindahl <marten.lindahl@axis.com>
Link: https://lore.kernel.org/r/20220428144039.2464667-2-marten.lindahl@axis.com


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