perf vendor events: Add JSON metrics for Ivy Town

Add JSON metrics for Ivy Town.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20170908180133.GA20128@tassilo.jf.intel.com


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