simpleperf: add type modifier when reporting events.

Before the change:
$simpleperf record -e cpu-cycles:u sleep 1
$simpleperf report
...
Event: cpu-cycles (type 0, config 0)
...

After the change:
$simpleperf report
...
Event: cpu-cycles:u (type 0, config 0)
...

Change-Id: I296c5476e03250e928ed0f579483d6866576d417
6 files changed