perf record: Improve 'Workload failed' message printing events + what was exec'ed

perf record: Improve 'Workload failed' message printing events + what was exec'ed

Before:

  # perf record -a cycles,instructions,cache-misses
  Workload failed: No such file or directory
  #

After:

  # perf record -a cycles,instructions,cache-misses
  Failed to collect 'cycles' for the 'cycles,instructions,cache-misses' workload: No such file or directory
  #

Helps disambiguating other error scenarios:

  # perf record -a -e cycles,instructions,cache-misses bla
  Failed to collect 'cycles,instructions,cache-misses' for the 'bla' workload: No such file or directory
  # perf record -a cycles,instructions,cache-misses sleep 1
  Failed to collect 'cycles' for the 'cycles,instructions,cache-misses' workload: No such file or directory
  #

When all goes well we're back to the usual:

  # perf record -a -e cycles,instructions,cache-misses sleep 1
  [ perf record: Woken up 3 times to write data ]
  [ perf record: Captured and wrote 3.151 MB perf.data (21242 samples) ]
  #

Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20210414131628.2064862-3-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>