firewire: mark some structs const

Instances of struct file_operations and struct fw_card_driver can be
qualified as "const".  Ditto with struct fw_descriptor.data, struct
fw_device_id, and predefined instances of struct fw_address_region,
at least in the current implementation.

Data qualified as const is placed into the .rodata section which won't
be mixed with dirty data.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/fw-device.h b/drivers/firewire/fw-device.h
index 731abbe..f39cf6a 100644
--- a/drivers/firewire/fw-device.h
+++ b/drivers/firewire/fw-device.h
@@ -113,7 +113,7 @@
 	struct device_driver driver;
 	/* Called when the parent device sits through a bus reset. */
 	void (*update) (struct fw_unit *unit);
-	struct fw_device_id *id_table;
+	const struct fw_device_id *id_table;
 };
 
 static inline struct fw_driver *
@@ -122,6 +122,6 @@
         return container_of(drv, struct fw_driver, driver);
 }
 
-extern struct file_operations fw_device_ops;
+extern const struct file_operations fw_device_ops;
 
 #endif /* __fw_device_h */