perf tools: Add some new tips describing the new options

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20190311144502.15423-9-andi@firstfloor.org


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