perf intel-pt: Fix system_wide dummy event for hybrid

User space tasks can migrate between CPUs, so when tracing selected CPUs,
system-wide sideband is still needed, however evlist->core.has_user_cpus
is not set in the hybrid case, so check the target cpu_list instead.

Fixes: 7d189cad ("perf intel-pt: Track sideband system-wide when needed")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20221012082259.22394-3-adrian.hunter@intel.com


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