perf metric: JSON flag to default metric group

perf metric: JSON flag to default metric group

For the default output, the default metric group could vary on different
platforms. For example, on SPR, the TopdownL1 and TopdownL2 metrics
should be displayed in the default mode. On ICL, only the TopdownL1
should be displayed.

Add a flag so we can tag the default metric group for different
platforms rather than hack the perf code.

The flag is added to Intel TopdownL1 since ICL and ADL, TopdownL2
metrics since SPR.

Add a new field, DefaultMetricgroupName, in the JSON file to indicate
the real metric group name.

Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ahmad Yasin <ahmad.yasin@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20230615135315.3662428-3-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>