SUNRPC: Ensure xprt_connect_status handles all potential connection errors

Currently, xprt_connect_status will convert connection error values such
as ECONNREFUSED, ECONNRESET, ... into EIO, which means that they never
get handled.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

net/sunrpc/xprt.c

@@ -749,6 +749,11 @@ static void xprt_connect_status(struct rpc_task *task)
 	}
 
 	switch (task->tk_status) {
+	case -ECONNREFUSED:
+	case -ECONNRESET:
+	case -ECONNABORTED:
+	case -ENETUNREACH:
+	case -EHOSTUNREACH:
 	case -EAGAIN:
 		dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid);
 		break;