perf tools: do not complain if root is owning perf.data

perf tools: do not complain if root is owning perf.data

This improves patch da05278f2 so that perf.data stuff that has
been dumped as root can be read (annotate/report) by a user
without the use of the --force.

Rationale is that root has plenty of ways to screw us (usually)
that do not require twisted schemes involving specially
crafting a perf.data.

Signed-off-by: Pierre Habouzit <pierre.habouzit@intersec.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <stable@kernel.org>
LKML-Reference: <20090827075902.GF19653@laphroaig.corp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>