In a famous exchange, a person was flustered and frustrated when asked to give a definition of pornography. In desperation the person answered: “I know it when I see it!”
There is pornography with racist content, so racism and pornography can intersect. Also, racist environments and attitudes may facilitate the production of pornography. However, your question asks whether they are in the "same category", which is too indefinite and needs some specification of the category or indication of constraints on what a relevant category might be, or perhaps of your purpose in raising the question. (Truly but trivially, they are both in the category of human activities, which for most intents and purposes is an otiose answer.)
My deepest apologies for the imprecision in the statement. I simply meant to say that both racism and pornography are difficult to define, and we may simply know it when we see it.