Brake pad has lowest life out of three (pads, drum and pump). which depends on your braking style. From 10k - 30k kms.
Brake drum has almost double or triple life than brake pads, depending on ur braking pattern (hard hitting always or u plan ur brake ahead).
Brake pump or booster has maximum life and will not go bad so fast, unless there is some problem in it.
So to answer your question you dont need to change brake ump with brake pad, but if brake pump is faulty or weak then you should change that irrespective of change with pads or drum. Its a separate issue all together. Dont get mixed up with different things.