rpc: Report proper close reason

Whenever client socket was marked as closed for some reason, it could've
been changed when really closing the connection.  With this patch the
proper reason is kept since the first time it's marked as closed.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

src/rpc/virnetclient.c

@@ -634,8 +634,11 @@ virNetClientMarkClose(virNetClientPtr client,
     VIR_DEBUG("client=%p, reason=%d", client, reason);
     if (client->sock)
         virNetSocketRemoveIOCallback(client->sock);
-    client->wantClose = true;
-    client->closeReason = reason;
+    /* Don't override reason that's already set. */
+    if (!client->wantClose) {
+        client->wantClose = true;
+        client->closeReason = reason;
+    }
 }