perf tools: Add cpumode to struct hist_entry

The next patch needs to sort on cpumode, so add it to hist_entry to be tracked.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/1401208087-181977-6-git-send-email-dzickus@redhat.com


Signed-off-by: Jiri Olsa <jolsa@kernel.org>