rxrpc: Fix a missing rxrpc_put_peer() in the error_report handler

Fix a missing call to rxrpc_put_peer() on the main path through the
rxrpc_error_report() function.  This manifests itself as a ref leak
whenever an ICMP packet or other error comes in.

In commit f3344303, the hand-off of the ref to a work item was removed
and was not replaced with a put.

Fixes: f3344303 ("rxrpc: Fix error distribution")
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/rxrpc/peer_event.c

@@ -195,6 +195,7 @@ void rxrpc_error_report(struct sock *sk)
 	rxrpc_store_error(peer, serr);
 	rcu_read_unlock();
 	rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+	rxrpc_put_peer(peer);
 
 	_leave("");
 }