perf stat: Exit perf stat if parse groups fails

perf stat: Exit perf stat if parse groups fails

Metrics were added by a callback but commit a4b8cfcabb1d90ec ("perf
stat: Delay metric parsing") postponed this to allow optimizations based
on the CPU configuration.

In doing so it stopped errors in metric parsing from causing 'perf stat'
termination.

This change adds the termination for bad metric names back in.

Fixes: a4b8cfcabb1d90ec ("perf stat: Delay metric parsing")
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Closes: https://lore.kernel.org/lkml/ZXByT1K6enTh2EHT@kernel.org/
Link: https://lore.kernel.org/r/20231206183533.972028-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>