simpletrace: add __all__ to define public interface

It was unclear what was the supported public interface. I.e. when
refactoring the code, what functions/classes are important to retain.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Mads Ynddal <m.ynddal@samsung.com>
Message-id: 20230926103436.25700-2-mads@ynddal.dk
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

scripts/simpletrace.py

@@ -14,6 +14,8 @@
 from tracetool import read_events, Event
 from tracetool.backend.simple import is_string
 
+__all__ = ['Analyzer', 'process', 'run']
+
 header_event_id = 0xffffffffffffffff
 header_magic    = 0xf2b177cb0aa429b4
 dropped_event_id = 0xfffffffffffffffe