tracing: Save one trace_event->type by using __TRACE_LAST_TYPE

Static defined trace_event->type stops at (__TRACE_LAST_TYPE - 1) and
dynamic trace_event->type starts from (__TRACE_LAST_TYPE + 1).

To save one trace_event->type index, let's use __TRACE_LAST_TYPE.

Link: https://lkml.kernel.org/r/20200703020612.12930-3-richard.weiyang@linux.alibaba.comSigned-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

kernel/trace/trace_output.c

@@ -20,7 +20,7 @@ DECLARE_RWSEM(trace_event_sem);
 
 static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
 
-static int next_event_type = __TRACE_LAST_TYPE + 1;
+static int next_event_type = __TRACE_LAST_TYPE;
 
 enum print_line_t trace_print_bputs_msg_only(struct trace_iterator *iter)
 {
@@ -675,7 +675,7 @@ static LIST_HEAD(ftrace_event_list);
 static int trace_search_list(struct list_head **list)
 {
 	struct trace_event *e;
-	int next = __TRACE_LAST_TYPE + 1;
+	int next = __TRACE_LAST_TYPE;
 
 	if (list_empty(&ftrace_event_list)) {
 		*list = &ftrace_event_list;