perf tests: Skip pipe test if noploop symbol is missing

perf tests: Skip pipe test if noploop symbol is missing

perf pipe recording and injection test depends on finding symbol noploop in
perf, and fails if perf has been stripped and no debug object is available.
In that case, skip the test instead.

Example:

 Before:

  $ strip tools/perf/perf
  $ tools/perf/perf buildid-cache -p `realpath tools/perf/perf`
  $ tools/perf/perf test -v pipe
   86: perf pipe recording and injection test                          :
  --- start ---
  test child forked, pid 47734
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.000 MB - ]
       47741    47741       -1 |perf
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.000 MB - ]
  cannot find noploop function in pipe #1
  test child finished with -1
  ---- end ----
  perf pipe recording and injection test: FAILED!

After:

  $ tools/perf/perf test -v pipe
   86: perf pipe recording and injection test                          :
  --- start ---
  test child forked, pid 48996
  perf does not have symbol 'noploop'
  perf is missing symbols - skipping test
  test child finished with -2
  ---- end ----
  perf pipe recording and injection test: Skip

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/20231123075848.9652-4-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>