eeprom: at24: Probe for DDR3 thermal sensor in the SPD case

eeprom: at24: Probe for DDR3 thermal sensor in the SPD case

The DDR3 SPD data structure advertises the presence of a thermal
sensor on a DDR3 module in byte 32, bit 7. Let's use this information
to explicitly instantiate the thermal sensor I2C client instead of
having to rely on class-based I2C probing.

The temp sensor i2c address can be derived from the SPD i2c address,
so we can directly instantiate the device and don't have to probe
for it. If the temp sensor has been instantiated already by other
means (e.g. class-based auto-detection), then the busy-check in
i2c_new_client_device will detect this.

Note: Thermal sensors on DDR4 DIMM's are instantiated from the
      ee1004 driver.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/68113672-3724-44d5-9ff8-313dd6628f8c@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>