SUNRPC: Handle EADDRINUSE on connect

Now that we're setting SO_REUSEPORT, we still need to handle the
case where a connect() is attempted, but the old socket is still
lingering.
Essentially, all we want to do here is handle the error by waiting
a few seconds and then retrying.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 3f5d4d4..612aa73 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -1826,6 +1826,7 @@
 	case -ECONNABORTED:
 	case -ENETUNREACH:
 	case -EHOSTUNREACH:
+	case -EADDRINUSE:
 	case -ENOBUFS:
 	case -EPIPE:
 		if (RPC_IS_SOFTCONN(task))
@@ -1934,6 +1935,7 @@
 		}
 	case -ECONNRESET:
 	case -ECONNABORTED:
+	case -EADDRINUSE:
 	case -ENOTCONN:
 	case -ENOBUFS:
 	case -EPIPE:
@@ -2053,6 +2055,7 @@
 	case -ECONNRESET:
 	case -ECONNABORTED:
 		rpc_force_rebind(clnt);
+	case -EADDRINUSE:
 	case -ENOBUFS:
 		rpc_delay(task, 3*HZ);
 	case -EPIPE: