rxrpc: Fix warning by splitting rxrpc_send_call_packet()

Split rxrpc_send_data_packet() to separate ACK generation (which is more
complicated) from ABORT generation.  This simplifies the code a bit and
fixes the following warning:

In file included from ../net/rxrpc/output.c:20:0:
net/rxrpc/output.c: In function 'rxrpc_send_call_packet':
net/rxrpc/ar-internal.h:1187:27: error: 'top' may be used uninitialized in this function [-Werror=maybe-uninitialized]
net/rxrpc/output.c:103:24: note: 'top' was declared here
net/rxrpc/output.c:225:25: error: 'hard_ack' may be used uninitialized in this function [-Werror=maybe-uninitialized]

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index 364b42d..0709401 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -498,7 +498,7 @@
 				  struct rxrpc_call, sock_link);
 		rxrpc_get_call(call, rxrpc_call_got);
 		rxrpc_abort_call("SKT", call, 0, RX_CALL_DEAD, ECONNRESET);
-		rxrpc_send_call_packet(call, RXRPC_PACKET_TYPE_ABORT);
+		rxrpc_send_abort_packet(call);
 		rxrpc_release_call(rx, call);
 		rxrpc_put_call(call, rxrpc_call_put);
 	}