hwmon: Drop non-functional I2C_CLASS_HWMON support for drivers w/o detect()

Class-based I2C probing requires detect() and address_list both
to be set in the I2C client driver, see checks in i2c_detect().
It's misleading to declare I2C_CLASS_HWMON support if the driver
doesn't implement detect().
Class-based probing is a legacy mechanism, in addition apparently
nobody ever noticed that class-based probing has been non-functional
in both drivers from the very beginning. So drop the fragments of
class-based probing support.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/13ce7c11-a958-4892-ada9-faf5bfdcb89d@gmail.com


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