Separate sudo io plugin symbols are created which stores wrapper
functions adding the context of which python plugin the callback is
about.
These sudo io plugin "slots" get generated with macros by the preprocessor.
This makes sudo support loading multiple python IO plugins like this:
(note the differences in the symbol names)
Plugin python_io python_plugin.so ModulePath=... ClassName=SudoIOPlugin1
Plugin python_io1 python_plugin.so ModulePath=... ClassName=SudoIOPlugin2
Plugin python_io2 python_plugin.so ModulePath=... ClassName=SudoIOPlugin3
