hwmon: (lm90) Add support for extra features of max6659

Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

Documentation/hwmon/lm90

@@ -101,10 +101,11 @@ well as the temperature of up to one external diode. It is compatible
 with many other devices, many of which are supported by this driver.
 
 Note that there is no easy way to differentiate between the MAX6657,
-MAX6658 and MAX6659 variants. The extra address and features of the
-MAX6659 are not supported by this driver. The MAX6680 and MAX6681 only
-differ in their pinout, therefore they obviously can't (and don't need to)
-be distinguished.
+MAX6658 and MAX6659 variants. The extra features of the MAX6659 are only
+supported by this driver if the chip is located at address 0x4d or 0x4e,
+or if the chip type is explicitly selected as max6659.
+The MAX6680 and MAX6681 only differ in their pinout, therefore they obviously
+can't (and don't need to) be distinguished.
 
 The specificity of this family of chipsets over the ADM1021/LM84
 family is that it features critical limits with hysteresis, and an