Merge remote-tracking branch 'stefanha/tracing' into staging

# By Markus Armbruster
# Via Stefan Hajnoczi
* stefanha/tracing:
  trace-events: Fix up source file comments
  trace-events: Drop unused events
  milkymist-minimac2: Fix minimac2_read/_write tracepoints
  slavio_misc: Fix slavio_led_mem_readw/_writew tracepoints
  cleanup-trace-events.pl: New

Message-id: 1374119369-26496-1-git-send-email-stefanha@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>