libperf: Handle read format in perf_evsel__read()

libperf: Handle read format in perf_evsel__read()

The perf_counts_values should be increased to read the new lost data.
Also adjust values after read according the read format.

This supports PERF_FORMAT_GROUP which has a different data format but
it's only available for leader events.  Currently it doesn't have an API
to read sibling (member) events in the group.  But users may read the
sibling event directly.

Also reading from mmap would be disabled when the read format has ID or
LOST bit as it's not exposed via mmap.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220819003644.508916-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>