firewire: remove bogus check in fw_core_handle_request
This check is bogus:
- Maximum asynchronous payload size for S800...S3200 is 4096.
- The p->payload_length is totally uninteresting. Only the
request->length of the subsequently allocated and initialized
struct fw_request is of significance.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Kristian Høgsberg <krh@redhat.com>