perf mem: Support AUX trace

perf mem: Support AUX trace

The 'perf mem' tool doesn't support AUX trace data so it cannot receive
the hardware tracing data.

On arm64, although it doesn't support PMU events for memory load and
store, ARM SPE is a good candidate for memory profiling, the hardware
tracer can record memory accessing operations with affiliated
information (e.g. physical address and virtual address for accessing,
cache levels, TLB walking, latency, etc).

To allow "perf mem" tool to support AUX trace, this patch adds the AUX
callbacks for session structure; make itrace memory event as default for
"perf mem", this tells the AUX trace decoder to synthesize memory
samples.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/r/20201106094853.21082-8-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>