perf: Fix UAPI export of PERF_EVENT_IOC_ID

Without the following patch I have problems compiling code using
the new PERF_EVENT_IOC_ID ioctl().  It looks like u64 was used
instead of __u64

Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1309171450380.11444@vincent-weaver-1.um.maine.edu
Signed-off-by: Ingo Molnar <mingo@kernel.org>