perf data convert ctf: Pipe mode improvements

perf data convert ctf: Pipe mode improvements

Handle the finished_round event. Set up the CTF events when the
feature event desc is read. In pipe mode the attr events will create
the evsels and the feature event desc events will name the evsels. The
CTF events need the evsel name, so wait until feature event descs are
read (in pipe mode) before setting up the events except for tracepoint
events. Handle the tracing_data event so that tracepoint information
is available when setting up tracepoint events.

Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>