Revert D30883290: [Static Runtime] Move MemoryPlanner out into memory_planner.cpp
Test Plan: revert-hammer
Differential Revision:
D30883290 (https://github.com/pytorch/pytorch/commit/0e11454d19e106ba6d5819c1147ca540cbce2943)
Original commit changeset: a37570f8d943
fbshipit-source-id: 65c57a2b0d2e3c7006765195dd519e8cf2472f72
