perf tools: Cleanup realloc use

The if branch is completely unnecessary since 'realloc' handles NULL
pointers for the first parameter.

This is really only a cleanup and submitted mainly to prevent
proliferation of bad practices.
Signed-off-by: Ulrich Drepper <drepper@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/201204231304.q3ND4TFe020805@drepperk.user.openhosting.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/header.c

@@ -31,21 +31,16 @@ static const char **header_argv;
 
 int perf_header__push_event(u64 id, const char *name)
 {
+	struct perf_trace_event_type *nevents;
+
 	if (strlen(name) > MAX_EVENT_NAME)
 		pr_warning("Event %s will be truncated\n", name);
 
-	if (!events) {
-		events = malloc(sizeof(struct perf_trace_event_type));
-		if (events == NULL)
-			return -ENOMEM;
-	} else {
-		struct perf_trace_event_type *nevents;
-
 	nevents = realloc(events, (event_count + 1) * sizeof(*events));
 	if (nevents == NULL)
 		return -ENOMEM;
 	events = nevents;
-	}
+
 	memset(&events[event_count], 0, sizeof(struct perf_trace_event_type));
 	events[event_count].event_id = id;
 	strncpy(events[event_count].name, name, MAX_EVENT_NAME - 1);