Synthesize new power and ptwrite events.

Power events report changes to C-state but I have also added support
for the existing CBR (core-to-bus ratio) packet and included that
when outputting power events.

The PTWRITE packet is associated with the new "ptwrite" instruction,
which is essentially just a way to stuff a 32 or 64 bit value into the
PT trace.

More details can be found in the patches that add documentation and in
the Intel SDM.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1498811805-2335-1-git-send-email-adrian.hunter@intel.com
[ Copy the description of such packet from the patchkit cover message ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>