staging/fwserial: Drop suggestion for helper fn integration

The firewire core does not require or want the suggested helper fns;
drop suggestion from TODO file.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/fwserial/TODO

@@ -12,8 +12,6 @@ TODOs prior to this driver moving out of staging
 1. This driver uses the same unregistered vendor id that the firewire core does
      (0xd00d1e). Perhaps this could be exposed as a define in
      firewire.h?
-3. Maybe device_max_receive() and link_speed_to_max_payload() should be
-     taken up by the firewire core?
 
 -- Issues with TTY core --
   1. Hack for alternate device name scheme