perf test: 'unwind' test should create kernel maps

perf test: 'unwind' test should create kernel maps

The 'perf test unwind' is failing because it forgot to create the kernel
maps, fix it.

After the patch:

  # perf test unwind
  40: Test dwarf unwind         : Ok

Reported-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20151127082121.GA24503@krava.brq.redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>