rxrpc, afs: Use debug_ids rather than pointers in traces

In rxrpc and afs, use the debug_ids that are monotonically allocated to
various objects as they're allocated rather than pointers as kernel
pointers are now hashed making them less useful.  Further, the debug ids
aren't reused anywhere nearly as quickly.

In addition, allow kernel services that use rxrpc, such as afs, to take
numbers from the rxrpc counter, assign them to their own call struct and
pass them in to rxrpc for both client and service calls so that the trace
lines for each will have the same ID tag.

Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index f38d6a5..7221717 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -118,6 +118,7 @@ struct afs_call {
 	bool			ret_reply0;	/* T if should return reply[0] on success */
 	bool			upgrade;	/* T to request service upgrade */
 	u16			service_id;	/* Actual service ID (after upgrade) */
+	unsigned int		debug_id;	/* Trace ID */
 	u32			operation_ID;	/* operation ID for an incoming call */
 	u32			count;		/* count for use in unmarshalling */
 	__be32			tmp;		/* place to extract temporary data */