perf evlist: Fix set event list leader
perf evlist: Fix set event list leader

The __perf_evlist__set_leader() was setting the leader for all events in
the list except the first. Which means it assumed the first event
already had event->leader = event.

Seems like this should be the role of the function to also do this. This
is a requirement for an upcoming patch set.

Signed-off-by: Stephane Eranian <f199ae9781930a5b94b284ca2f471140752002a7@google.com>
Acked-by: Jiri Olsa <2c6594f608aa3d41e98d48846a6328831f7084ad@redhat.com>
Tested-by: Jiri Olsa <2c6594f608aa3d41e98d48846a6328831f7084ad@redhat.com>
Acked-by: Namhyung Kim <5c915a589b3ddf58cebf14bec41bcc143b37ac3c@kernel.org>
Cc: Ingo Molnar <9dbbbf0688fedc85ad4da37637f1a64b8c718ee2@elte.hu>
Cc: Jiri Olsa <2c6594f608aa3d41e98d48846a6328831f7084ad@redhat.com>
Cc: Namhyung Kim <1b20bcb62cf1b100c528e605608922000dc2fc80@lge.com>
Cc: Peter Zijlstra <3fddac958924aef220f202ca567388ddab3f14a8@infradead.org>
Link: e4f5f5571f5ecfc83f32398c35681a22f276eb47@quad
Signed-off-by: Arnaldo Carvalho de Melo <293abb6b76d7791c0732cc517d38c4b5c734b87f@redhat.com>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs