libperf evlist: Move ->idx() into mmap_per_evsel()

mainline inclusion
from mainline-v5.19-rc1
commit d8fe2efb
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I7HI80
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d8fe2efb65acdc213eb180b7853fc1121c1bff37



--------------------------------

Remove ->idx() per_cpu parameter because it isn't needed.
Move ->idx() into mmap_per_evsel() in preparation for adding evsel as a
parameter.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20220506122601.367589-8-adrian.hunter@intel.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Junhao He <hejunhao3@huawei.com>