perf top: Use parse_options_usage() for -s option failure

perf top: Use parse_options_usage() for -s option failure

The -s (--sort) option was processed after normal option parsing so that
it cannot call the parse_options_usage() automatically.  Currently it
calls usage_with_options() which shows entire help messages for event
option.  Fix it by showing just -s options.

  $ perf top -s help
    Error: Unknown --sort key: `help'

   usage: perf top [<options>]

      -s, --sort <key[,key2...]>
                            sort by key(s): pid, comm, dso, symbol, ...

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Enthusiastically-Supported-by: Ingo Molnar <mingo@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1383291195-24386-5-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>