Neosporin?

Definitely no on the Neosporin. It can irritate him and cause him to scratch at the wound, worsening it.

The best thing to do is clean it off with warm water and let it heal on its own.

I have used a small, tiny, itty bitty little squirt of Bactine on a q-tip to clean a wound on my youngest pig, but that it because it was on his rear, therefore more at risk for infection. He didn't like it at all.

If the wound is severe, he should see a vet. If it is just a minor scrape, let nature work its magic. Just keep a close eye on it.