Give lifted primitive types a representation
As of D1774 everything in GHC.Prim has a representation generated for it
by TcTypeable (see Trac #11120). Unfortunately I evidently missed propagating
this change to lifted primitive types. This patch fixes this (Trac #12082).
Test Plan: Validate
Differential Revision: https://phabricator.haskell.org/D2240
GHC Trac Issues: Trac #12082