perf evsel: Move id_offset out of struct perf_evsel union member

Because the 'perf stat record' patches will use the id_offset member
together with the priv pointer.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Kan Liang <kan.liang@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1445784728-21732-29-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/evsel.h

@@ -90,9 +90,9 @@ struct perf_evsel {
 	double			scale;
 	const char		*unit;
 	struct event_format	*tp_format;
+	off_t			id_offset;
 	union {
 		void		*priv;
-		off_t		id_offset;
 		u64		db_id;
 	};
 	struct cgroup_sel	*cgrp;