For some ARCHs, e.g., ARM and AMD, to get the availability of the
mem-events, perf checks the existence of a specific PMU. For the other
ARCHs, e.g., Intel and Power, perf has to check the existence of some
specific events.

The current perf only iterates the mem-events-supported PMUs. It's not
required to check the existence of a specific PMU anymore.

Rename sysfs_name to event_name, which stores the specific mem-events.
Perf only needs to check those events for the availability of the
mem-events.

Rename perf_mem_event__supported to perf_pmu__mem_events_supported.
Reviewed-by: Ian Rogers <irogers@google.com>
Tested-by: Ravi Bangoria <ravi.bangoria@amd.com>
Tested-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: james.clark@arm.com
Cc: will@kernel.org
Cc: mike.leach@linaro.org
Cc: renyu.zj@linux.alibaba.com
Cc: yuhaixin.yhx@linux.alibaba.com
Cc: tmricht@linux.ibm.com
Cc: atrajeev@linux.vnet.ibm.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: john.g.garry@oracle.com
Link: https://lore.kernel.org/r/20240123185036.3461837-5-kan.liang@linux.intel.comSigned-off-by: Namhyung Kim <namhyung@kernel.org>