tracing: Pass trace_array into trace_buffer_unlock_commit()

In preparation for having trace options be per instance, the trace_array
needs to be passed to the trace_buffer_unlock_commit(). The
trace_event_buffer_lock_reserve() already passes in the trace_event_file
where the trace_array can be derived from.

Also added a "__init" to the boot up test event plus function tracing
function function_test_events_call().

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>