perf annotate-data: Ensure the number of type histograms

perf annotate-data: Ensure the number of type histograms

Arnaldo reported that there is a case where nr_histograms and histograms
don't agree each other.

It ended up in a segfault trying to access a NULL histograms array.

Let's make sure to update the nr_histograms when the histograms array is
changed.

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
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: 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/20240510210452.2449944-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>