Move the libcall annotating part from doFinalization to doInitialization.

Move the libcall annotating part from doFinalization to doInitialization.
Finalization occurs after all the FunctionPasses in the group have run, which
is clearly not what we want.

This also means that we have to make sure that we apply the right param
attributes when creating a new function.

Also, add a missed optimization: strdup and strndup. NoCapture and
NoAlias return!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61658 91177308-0d34-0410-b5e6-96231b3b80d8