tree-wide: fix a number of log calls that use %m but have no errno set

This is mostly fall-out from d1a1f0aaf0,
however some cases are older bugs.

There might be more issues lurking, this was a simple grep for "%m"
across the tree, with all lines removed that mention "errno" at all.

src/network/netdev/netdev.c

@@ -242,7 +242,7 @@ static int netdev_enslave_ready(NetDev *netdev, Link* link, sd_netlink_message_h
 
         r = sd_netlink_call_async(netdev->manager->rtnl, req, callback, link, 0, NULL);
         if (r < 0)
-                return log_netdev_error(netdev, "Could not send rtnetlink message: %m");
+                return log_netdev_error_errno(netdev, r, "Could not send rtnetlink message: %m");
 
         link_ref(link);