perf mem: Fix --all-user/--all-kernel options

Removing extra '--' prefix.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Fixes: ad16511b ("perf mem: Add -U/-K (--all-user/--all-kernel) options")
Link: http://lkml.kernel.org/r/1481538943-21874-2-git-send-email-jolsa@kernel.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>