perf test: perf data --to-ctf testing

perf test: perf data --to-ctf testing

If babeltrace is detected check that --to-ctf functions with a data
file and in pipe mode.

Committer testing:

  $ perf test 'perf data convert --to-ctf'
  124: 'perf data convert --to-ctf' command test                       : Ok
  $ perf test -vv 'perf data convert --to-ctf'
  124: 'perf data convert --to-ctf' command test:
  --- start ---
  test child forked, pid 556008
           libbabeltrace: [ on  ]  # HAVE_LIBBABELTRACE_SUPPORT
  Testing Perf Data Conversion Command to CTF (File input)
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.021 MB /tmp/__perf_test.perf.data.9TxzZ (115 samples) ]
  [ perf data convert: Converted '/tmp/__perf_test.perf.data.9TxzZ' into CTF data '/tmp/__perf_test.ctf.f5EkS' ]
  [ perf data convert: Converted and wrote 0.012 MB (115 samples) ]
  Perf Data Converter Command to CTF (File input) [SUCCESS]
  Testing Perf Data Conversion Command to CTF (Pipe mode)
  [ perf record: Woken up 2 times to write data ]
  [ perf record: Captured and wrote 0.047 MB - ]
  Failed to setup all events.
  [ perf data convert: Converted '/tmp/__perf_test.perf.data.9TxzZ' into CTF data '/tmp/__perf_test.ctf.f5EkS' ]
  [ perf data convert: Converted and wrote 0.000 MB (0 samples) ]
  Perf Data Converter Command to CTF (Pipe mode) [SUCCESS]
  Unexpected signal in main
  ---- end(0) ----
  124: 'perf data convert --to-ctf' command test                       : Ok
  $

Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Derek Foreman <derek.foreman@collabora.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>