perf script python: Add script to profile and resolve physical mem type

There could be different types of memory in the system. E.g normal
System Memory, Persistent Memory. To understand how the workload maps to
those memories, it's important to know the I/O statistics of them. Perf
can collect physical addresses, but those are raw data. It still needs
extra work to resolve the physical addresses. Provide a script to
facilitate the physical addresses resolving and I/O statistics.

Profile with MEM_INST_RETIRED.ALL_LOADS or MEM_UOPS_RETIRED.ALL_LOADS
event if any of them is available.

Look up the /proc/iomem and resolve the physical address. Provide
memory type summary.

Here is an example output:

# perf script report mem-phys-addr
Event: mem_inst_retired.all_loads:P
Memory type count percentage
---------------------------------------- ----------- -----------
System RAM 74 53.2%
Persistent Memory 55 39.6%
N/A

---

Changes since V2:
- Apply the new license rules.
- Add comments for globals

Changes since V1:
- Do not mix DLA and Load Latency. Do not compare the loads and stores.
Only profile the loads.
- Use event name to replace the RAW event

Signed-off-by: Kan Liang <Kan.liang@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lkml.kernel.org/r/1515099595-34770-1-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>