perf annotate-data: Implement folding in TUI browser

Like 'perf report', use 'e' or 'E' key to toggle folding the current
entry so that it can control displaying child entries.

Note I didn't add the 'c' and 'C' key to collapse the entry because it's
also handled with the 'e'/'E' since it toggles the state.

Committer testing:

Do some 'perf mem record' for some workload of the whole system, using
the target options, as usual (--pid/-p, -C/--cpu, -a for the system wide
profiling, etc) and then:

  # perf annotate --skip-empty --data-type=pthread_mutex_t

That, by default, will start as --tui, then press 'E' to see the whole
struct unfolded, etc.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240812194447.2049187-3-namhyung@kernel.org


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