perf record: Fix sample cgroup & namespace tracking

perf record: Fix sample cgroup & namespace tracking

The recent change in 'struct perf_tool' constification broke the cgroup
and/or namespace tracking by resetting tool fields.  It should set the
values after perf_tool__init().

Fixes: cecb1cf154b301c6 ("perf record: Use perf_tool__init()")
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
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/20240818212948.2873156-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>