perf test perftool_testsuite: Return correct value for skipping

perf test perftool_testsuite: Return correct value for skipping

In 'perf test', a return value 2 represents that the test case was
skipped. Fix this value for perftool_testsuite test cases to
differentiate between skip and pass values.

Signed-off-by: Veronika Molnarova <vmolnaro@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20250113182605.130719-3-vmolnaro@redhat.com
Signed-off-by: Michael Petlan <mpetlan@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>