perf probe: Accept filter argument for --funcs

This allows the user to pass the filter pattern directly to the --funcs
option as below:

  ----
  # ./perf probe -F *kmalloc
  __kmalloc
  devm_kmalloc
  mempool_kmalloc
  sg_kmalloc
  sock_kmalloc
  ----

We previously needed to use the --filter option for that.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150505022950.23399.22435.stgit@localhost.localdomain


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