dnos10.pm: filter fan speed for second fan on same tray

[spike77453]

This patches dnos10.pm to filter out the fan speed if there's a second fan for any specify fan tray present, e.g. on S5200 devices such as the S5232F and S5248F where raw data might look like this:

-- Fan Status --
FanTray  Status      AirFlow   Fan  Speed(rpm)  Status
----------------------------------------------------------------
1        up          REVERSE   1    8520        up         
                               2    7680        up         

2        up          REVERSE   1    8640        up         
                               2    7680        up         

3        up          REVERSE   1    8640        up         
                               2    7680        up         

4        up          REVERSE   1    8520        up         
                               2    7800        up         

[haussli]

merged. thanks!