We pass fsevent_callback() to the system FSEventStreamCreate() function
as a callback. So we must match the expected function signature, even
though we don't care about all of the parameters. Mark the unused ones
to satisfy -Wunused-parameter.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>