add_function doesn't use custom_name for generated wrapper code

[Kevin Stenerson]

The Module.add_function method uses the normal name instead of the custom_name for the generated wrapper function's name.

Class.add_method handles this correctly so that if I were to call the following:
    cls.add_method('get_foo', retval('int'), [])
    cls.add_method('get_foo', retval('int'), [], custom_name = 'getFoo')

It produces:
    _wrap_PyModulenameClassname_get_foo
    _wrap_PyModulenameClassname_getFoo

However, the same thing with add_function:
    mod.add_function('get_foo', retval('int'), [])
    mod.add_function('get_foo', retval('int'), [], custom_name = 'getFoo')

Will produce:
    _wrap_modulename_get_foo
    _wrap_modulename_get_foo

and cause the error:
  redefinition of ‘PyObject* _wrap_modulename_get_foo(PyObject*)’

[Kevin Stenerson (stenersonkevin)]

Submitting patch.

[Gustavo Carneiro (gjc)]

Thank you.