Fix loopback interfaces support - missing braces in if

[koby08]

Missing if braces caused to skip the interface, even if it's IFF_LOOPBACK (only the log print is inside the if clause)

[koby08]

@troglobit appreciate if you can take a look.. thanks!

[troglobit]

It's in my backlog, albeit with a low priority. I'll see when I can have a look and test your patch.

[koby08]

@troglobit friendly reminder :) Note it's a small local change - easy to get convinced that the IFF_LOOPBACK check is not related to the generated log and the current code doesn't make sense