This is dumb, Hispanic isn't a race
There are white hispanics, black hispanics and indigenous hispanics.
But because popular culture considers "hispanic" to be a brown skinned Mexican, that means they should be a seperate race. Thats dumb (most Mexicans are mixed with white and indigenous thus the brown skin)
There are also Middle Eastern and Asian Hispanics, but that's not the point. A person's race is whatever a society perceives them to be - a Coloured South African would be considered black in the US, while an Iranian would be considered white in Africa. Nobody is forcing anyone to identify in a certain way - they are free to select any combination.
The only other practical solutions to correctly addressing the huge Hispanic population in the US is to either stop tracking race entirely or create a mestizo category, which would be creating a new race that isn't widely recognized in American society.