Fix a corner case when printing unaccounted time

Previously `ra_prof` wouldn't actually print the unaccounted time in
some cases.

We would print, for instance, this:
```
    5ms - foo
        2ms - bar
```
instead of:
```
    5ms - foo
        2ms - bar
        3ms - ???
```

The fix is to properly handle the case when an entry has 0 children
instead of using the `last` variable.

Signed-off-by: Michal Terepeta <[email protected]>

0 files changed, 0 insertions, 0 deletions