Only throw -fPIC when building a shared library

Summary:
Update makefiles to specify -fPIC in Makefile.rules and only throw -fPIC when building a shared library. This change is necessary to allow building the lldb tests on Windows where -fPIC is not a valid option. 

Update a few places to Python 3.x syntax


Reviewers: zturner, lldb-commits

Reviewed By: zturner

Subscribers: stella.stamenova, labath, llvm-commits

Differential Revision: https://reviews.llvm.org/D42994

llvm-svn: 324671