perf tests: Skip Arm64 callgraphs test if leafloop symbol is missing

The test "Check Arm64 callgraphs are complete in fp mode" depends on
finding symbol leafloop in perf, and fails if perf has been stripped and no
debug object is available. In that case, skip the test instead.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20231123075848.9652-6-adrian.hunter@intel.com


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