Nobody is going to care.
Sometimes I do look at candidates github repos before an interview (if they provide them on their resume). Even when the code is not great, it's still a positive sign because it lets me know they are writing and pushing code, not just talking about it. I don't think I've ever had less of an impression of a candidate from looking at their github, although I've had some confirm my expectations from their resume.
Worst case, let's say I was looking at someone's code, and I thought, as your example, maybe he doesn't understand linked lists.. hmm. I wouldn't dismiss them, I would ask that as an interview question.
If you're still nervous, ask a friend or colleague to give your code a quick code review (email me if you'd like my opinion), and grant them bitbucket access. Ask them if you think the code needs any cleanup before making it public.