firewire: remove an unused function argument

void (*fw_address_callback_t)(..., int speed, ...) is the speed that a
remote node chose to transmit a request to us.  In case of split
transactions, firewire-core will transmit the response at that speed.

Upper layer drivers on the other hand (firewire-net, -sbp2, firedtv, and
userspace drivers) cannot do anything useful with that speed datum,
except log it for debug purposes.  But data that is merely potentially
(not even actually) used for debug purposes does not belong into the API.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/include/linux/firewire.h b/include/linux/firewire.h
index 5553018..e44b502 100644
--- a/include/linux/firewire.h
+++ b/include/linux/firewire.h
@@ -265,7 +265,7 @@
 typedef void (*fw_address_callback_t)(struct fw_card *card,
 				      struct fw_request *request,
 				      int tcode, int destination, int source,
-				      int generation, int speed,
+				      int generation,
 				      unsigned long long offset,
 				      void *data, size_t length,
 				      void *callback_data);