remove loopback 127.0.0.1 from sys.ip_addresses

It has no discovery value for reporting and configuration.
One can always avoid this unsafety:
```
for (Rlist *rp = *ips_p; rp != NULL; )
{
    Rlist *here = rp;
    rp = rp->next;
    if (strcmp(RlistScalarValue(here), ...) == 0) { RlistDestroyEntry(ips_p, here); }
}
```
This ensures duplicates of the removed entry also get removed; and is all the more important if you change the `strcmp(...) == 0` to ```StringStartsWith(..., "127.0.0.")``` so as to catch the full /8 range.