physical: Fix readability-redundant-control-flow

```
/home/andrew/src/openbmc/phosphor-led-sysfs/build/../physical.cpp:57:5: error: redundant return statement at the end of a function with a void return type [readability-redundant-control-flow,-warnings-as-errors]
    return;
    ^~~~~~~
/home/andrew/src/openbmc/phosphor-led-sysfs/build/../physical.cpp:100:5: error: redundant return statement at the end of a function with a void return type [readability-redundant-control-flow,-warnings-as-errors]
    return;
~~~~^~~~~~~
/home/andrew/src/openbmc/phosphor-led-sysfs/build/../physical.cpp:123:5: error: redundant return statement at the end of a function with a void return type [readability-redundant-control-flow,-warnings-as-errors]
    return;
~~~~^~~~~~~
```

Change-Id: I58bf70aa3d565a0449e4c0a85b271512a0cf9742
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
1 file changed