hwmon: (w83627ehf) Describe undocumented pwm attributes

Add description of pwm[1-4]_start_output, pwm[1-4]_step_output,
pwm[1-4]_stop_output, and pwm[1-4]_max_output attributes to driver
documentation.

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

Documentation/hwmon/w83627ehf

@@ -143,8 +143,13 @@ pwm[1-4]_min_output - minimum fan speed (range 1 - 255), when the temperature
 pwm[1-4]_stop_time  - how many milliseconds [ms] must elapse to switch
                       corresponding fan off. (when the temperature was below
                       defined range).
+pwm[1-4]_start_output-minimum fan speed (range 1 - 255) when spinning up
+pwm[1-4]_step_output- rate of fan speed change (1 - 255)
+pwm[1-4]_stop_output- minimum fan speed (range 1 - 255) when spinning down
+pwm[1-4]_max_output - maximum fan speed (range 1 - 255), when the temperature
+                      is above defined range.
 
-Note: last two functions are influenced by other control bits, not yet exported
+Note: last six functions are influenced by other control bits, not yet exported
       by the driver, so a change might not have any effect.
 
 Implementation Details