perf tools: Pass build_id object to dso__set_build_id()

Passing build_id object to dso__set_build_id(), so it's easier
to initialize dos's build id object.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20201013192441.1299447-6-jolsa@kernel.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>