Desugar static forms to makeStatic calls.
Summary:
Using makeStatic instead of applications of the StaticPtr data
constructor makes possible linting core when unboxing strict
fields.
Test Plan: ./validate
Reviewers: simonpj, goldfire, austin, bgamari, hvr
Reviewed By: simonpj
Subscribers: RyanGlScott, mboes, thomie
Differential Revision: https://phabricator.haskell.org/D2930
GHC Trac Issues: Trac #12622