[PM] Add a nice low-tech registry of passes as a boring macro expansion
file. This will make it easy to scale up the number of passes supported.
Currently, it just supports the function and module transformation
passes that were already supported in the opt tool explicitly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206737 91177308-0d34-0410-b5e6-96231b3b80d8