Some black guy is claiming that it began around 2004 with some other black dude, a rapper maybe, but this was just an anecdotal claim. He didn't provide any text or video documentation to support his claim.
I also disagree with Timm See's statement that 'no homo' can be used before or after the potentially homo statement. It's after, always. No homo.
And there's nothing wrong with black guys wearing pink. Entire pink outfits might be a bit suspect, but as long as he's not wearing earrings, then he's not likely to be more than 50% gay.