perf tools: Move event prototypes from util.h to event.h

More needs to be done to have the actual functions and variables in a
smaller .c file that can then be included in the python binding,
avoiding dragging more stuff into it.

Link: http://lkml.kernel.org/n/tip-uecxz7cqkssouj7tlxrkqpl4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 0e87909..e4f7902 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -21,6 +21,7 @@
 #include "asm/bug.h"
 #include "callchain.h"
 #include "cgroup.h"
+#include "event.h"
 #include "evsel.h"
 #include "evlist.h"
 #include "util.h"