Question

I’m done working for the man, what kind of figurative language is this

Answer 1

Personification

Answer 2

I don't see any non-human involved in that statement.

I see it as a part of a dialect.

Answer 3

It could be considered synecdoche, in which "the man" means "the government." However, whether it's a form of synecdoche depends on the context. One sentence hardly tells us anything.

http://literary-devices.com/content/synecdoche