tracing: Rename (un)register_ftrace_event() to (un)register_trace_event()

The name "ftrace" really refers to the function hook infrastructure. It
is not about the trace_events. The functions (un)register_ftrace_event() is
really about trace_events, and the name should be register_trace_event()
instead.

Also renamed ftrace_event_reg() to trace_event_reg() for the same reason.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/include/trace/perf.h b/include/trace/perf.h
index 5e82add..bb751a5 100644
--- a/include/trace/perf.h
+++ b/include/trace/perf.h
@@ -69,7 +69,7 @@
  *	.fields			= LIST_HEAD_INIT(event_class_##call.fields),
  *	.raw_init		= trace_event_raw_init,
  *	.probe			= ftrace_raw_event_##call,
- *	.reg			= ftrace_event_reg,
+ *	.reg			= trace_event_reg,
  * };
  *
  * static struct ftrace_event_call event_<call> = {
@@ -219,7 +219,7 @@
 	.fields			= LIST_HEAD_INIT(event_class_##call.fields),\
 	.raw_init		= trace_event_raw_init,			\
 	.probe			= ftrace_raw_event_##call,		\
-	.reg			= ftrace_event_reg,			\
+	.reg			= trace_event_reg,			\
 	_TRACE_PERF_INIT(call)						\
 };