perf tools: Kill event_t typedef, use 'union perf_event' instead

And move the event_t methods to the perf_event__ too.

No code changes, just namespace consistency.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
index 6713725..1a79df9 100644
--- a/tools/perf/util/callchain.h
+++ b/tools/perf/util/callchain.h
@@ -95,8 +95,8 @@
 int callchain_merge(struct callchain_cursor *cursor,
 		    struct callchain_root *dst, struct callchain_root *src);
 
-bool ip_callchain__valid(struct ip_callchain *chain, const event_t *event);
-
+bool ip_callchain__valid(struct ip_callchain *chain,
+			 const union perf_event *event);
 /*
  * Initialize a cursor before adding entries inside, but keep
  * the previously allocated entries as a cache.