This Charles Bronson western followed only about a year after his western Chato's Land (1972) where his character had a similar name. Bronson was called Chino in this film and Chato in the earlier film.
One poster for this movie shows a drawing of a bare-chested Charles Bronson tied with upraised arms to a T-shaped whipping post. This differs from the scene in the movie in which Bronson is whipped while hanging suspended by his wrists from an overhead crossbeam. While two separate whipping scenes may have been shot (and one discarded), a more likely explanation is that the artist designing an early version of the "Chino" poster had not seen the actual movie and was only working from incomplete or misleading script notes.
The meaning and relevance of this movie's 'Chino' title is that Chino refers to the first name of the central character, Chino Valdez, played by Charles Bronson. The title 'Valdez, the Halfbreed' refers to this character's mixed Native American Indian / white European genealogy. Moreover, the title 'The Valdez Horses' refers to Chino's equine herd that he tames, breeds and trains.