There are no links between the two. They are two entirely different ailments. I have never heard
of men having yeast infections, but to think that there is a link between HIV and a yeast infection, has no merit.
Yeast infections are the result of a common fungus, which most healthy bodies repel. Individuals who are HIV positive have compromised immune systems, thus opening the door for opportunistic infections like thrush and other related fungal infections.
HIV weakens your immunity slightly so it's likely that you will get sick a lot. In your uncles case, it would be that he gets yeast infections a lot. The best thing that someone can do with HIV is just avoid anything that would get them sick or give them yeast infections.