qerror: Eliminate QERR_ macros used in just one place

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201113082626.2725812-3-armbru@redhat.com>
diff --git a/net/net.c b/net/net.c
index 6a2c3d9..e1035f2 100644
--- a/net/net.c
+++ b/net/net.c
@@ -1013,7 +1013,7 @@
     if (net_client_init_fun[netdev->type](netdev, netdev->id, peer, errp) < 0) {
         /* FIXME drop when all init functions store an Error */
         if (errp && !*errp) {
-            error_setg(errp, QERR_DEVICE_INIT_FAILED,
+            error_setg(errp, "Device '%s' could not be initialized",
                        NetClientDriver_str(netdev->type));
         }
         return -1;