perf c2c: Support memory event PERF_MEM_EVENTS__LOAD_STORE

perf c2c: Support memory event PERF_MEM_EVENTS__LOAD_STORE

When user doesn't specify event name, perf c2c tool enables both the
load and store events, and this leads to failure for opening the
duplicate PMU device for AUX trace.

After the memory event PERF_MEM_EVENTS__LOAD_STORE is introduced, when
the user doesn't specify event name, this patch converts the required
operation to PERF_MEM_EVENTS__LOAD_STORE if the arch supports it.
Otherwise, the tool still rolls back to enable events
PERF_MEM_EVENTS__LOAD and PERF_MEM_EVENTS__STORE.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/r/20201106094853.21082-5-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>