[PM] Simplify the IR printing passes significantly now that a narrower
API is exposed.

This removes the support for deleting the ostream, switches the member
and constructor order arround to be consistent with the creation
routines, and switches to using references.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199047 91177308-0d34-0410-b5e6-96231b3b80d8