perf tools: Fix perf_evsel::exclude_GH handling

Let the perf_evsel::exclude_GH only prevent the reset of exclude_host
and exclude_guest attributes in case they were already set.

We cannot reset their values to 0, because they might have other
defaults set by event_attr_init.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1359971803-2343-2-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/parse-events.c

@@ -699,14 +699,6 @@ static int get_event_modifier(struct event_modifier *mod, char *str,
 	int exclude = eu | ek | eh;
 	int exclude_GH = evsel ? evsel->exclude_GH : 0;
 
-	/*
-	 * We are here for group and 'GH' was not set as event
-	 * modifier and whatever event/group modifier override
-	 * default 'GH' setup.
-	 */
-	if (evsel && !exclude_GH)
-		eH = eG = 0;
-
 	memset(mod, 0, sizeof(*mod));
 
 	while (*str) {