Clean-up: silence warnings for generated code on RHEL8

Clean-up: silence warnings for generated code on RHEL8

  lttng_wrap.lo -MD -MP -MF .deps/lttng_wrap.Tpo -c lttng_wrap.c  -fPIC -DPIC -o .libs/lttng_wrap.o
  lttng_wrap.c:1824:23: warning: cast between incompatible function types from ‘PyObject * (*)(PyObject *)’ {aka ‘struct _object * (*)(struct _object *)’} to ‘PyObject * (*)(PyObject *, PyObject *)’ {aka ‘struct _object * (*)(struct _object *, struct _object *)’} [-Wcast-function-type]
     {(char *)"disown",  (PyCFunction)SwigPyObject_disown,  METH_NOARGS,  (char *)"releases ownership of the pointer"},
                         ^

Change-Id: I9258a58317814fdc94c8ce3c76e615b73aaf4199
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>