perf record: Move 'group' to perf_event_ops

Will be used in other tools to share the command line parsing code.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-8x0yr77r6lrd2t699s499m8n@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/perf.h b/tools/perf/perf.h
index 13c42f3..ea804f5 100644
--- a/tools/perf/perf.h
+++ b/tools/perf/perf.h
@@ -189,6 +189,7 @@
 	pid_t	     target_pid;
 	pid_t	     target_tid;
 	bool	     call_graph;
+	bool	     group;
 	bool	     inherit_stat;
 	bool	     no_delay;
 	bool	     no_inherit;