[jit] Break interpreter.cpp into smaller files. (#56546)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/56546
A code move for CodeImpl and Frame to a subdirectory runtime/interpreter, so
that it's easier to reuse them and navigate the interpreter code.
Test Plan: Imported from OSS
Reviewed By: nikithamalgifb
Differential Revision: D28133580
fbshipit-source-id: 8de89a4e8e637836625e1ac1db95f0a3353da670
