fix up dupe chmod

meant to be working on parent dir.
Use local copy of perf_event.h

Attached is an updated patch that adds perf_event.h from linux-3.10-rc4,
updates syscalls/perf_event_open.c to remove all ifdefs, and removes
the perf_event detection code from configure.sh

This will allow the perf_event_open code to compile on my machine
(and not depend on a possibly old version of linux/perf_event.h)
plus give some extra coverage by testing the added attr fields
on older kernels.

Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>