perf probe: Fix error reported when offset without function
perf probe: Fix error reported when offset without function

This patch fixes a bug that, when offset is provided but function is
lost, parse_perf_probe_point() will give a "" string as function name,
so the checking code at the end of parse_perf_probe_point() become
useless.  For example:

  # perf probe +0x1234
  Failed to find symbol  in kernel
    Error: Failed to add events.

After this patch:

  # perf probe +0x1234
  Semantic error :Offset requires an entry function.
    Error: Command Parse Error.

Signed-off-by: Wang Nan <7b589a40e0ecd4816b422e8ed1f74a01c34bf6bb@huawei.com>
Acked-by: Masami Hiramatsu <60fcdccfd958d359debfe6e6e7417cd7f1aaa9e3@hitachi.com>
Cc: Namhyung Kim <5c915a589b3ddf58cebf14bec41bcc143b37ac3c@kernel.org>
Cc: Steven Rostedt <43232e92d70cc7aa53504ad0397085ee47bad87f@goodmis.org>
Cc: Zefan Li <a8167b9d27aca9c6624754deb52c4c6420eded04@huawei.com>
Cc: d3a709cba82ff13e91126748cd399b3cb8e95d2e@163.com
Link: http://lkml.kernel.org/r/1440586666-235233-6-git-send-email-7b589a40e0ecd4816b422e8ed1f74a01c34bf6bb@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <293abb6b76d7791c0732cc517d38c4b5c734b87f@redhat.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs