perf timechart: Show the name of the waker/wakee in timechart

Timechart currently shows thin green lines for sending or receiving
wakeups. This patch also prints (in a very small font) the name of
the process that is being woken/wakes up this process.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20090920181328.68baa978@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>