physical: Fix bugprone-narrowing-conversions

```
/home/andrew/src/openbmc/phosphor-led-sysfs/build/../physical.cpp:120:20: error: narrowing conversion from 'double' to 'unsigned long' [bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions,-warnings-as-errors]
    led.setDelayOn(dutyOn * factor);
                   ^
/home/andrew/src/openbmc/phosphor-led-sysfs/build/../physical.cpp:121:21: error: narrowing conversion from 'double' to 'unsigned long' [bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions,-warnings-as-errors]
    led.setDelayOff((100 - dutyOn) * factor);
                    ^
```

Change-Id: Ic7dbacac3b636a209a743063182d324165bbbaa1
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
1 file changed