perf record: Honour --no-time command line option

perf record: Honour --no-time command line option

Time stamps are always implicitely enabled for record currently.  The
old --time/-T option is a nop.

Allow the user to disable timestamps by using --no-time, honouring the
existing option.

The defaults are unchanged.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1406789104-25863-10-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>