virtio: del net client if net_init_tap_one failed

If the net tap initializes successful, but failed during
network card hot-plugging, the net-tap will remains,
so cleanup.

Signed-off-by: lu zhipeng <luzhipeng@cestc.cn>
Signed-off-by: Jason Wang <jasowang@redhat.com>

net/tap.c

@@ -686,7 +686,7 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer,
     tap_set_sndbuf(s->fd, tap, &err);
     if (err) {
         error_propagate(errp, err);
-        return;
+        goto failed;
     }
 
     if (tap->has_fd || tap->has_fds) {
@@ -726,12 +726,12 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer,
                 } else {
                     warn_report_err(err);
                 }
-                return;
+                goto failed;
             }
             if (!g_unix_set_fd_nonblocking(vhostfd, true, NULL)) {
                 error_setg_errno(errp, errno, "%s: Can't use file descriptor %d",
                                  name, fd);
-                return;
+                goto failed;
             }
         } else {
             vhostfd = open("/dev/vhost-net", O_RDWR);
@@ -743,11 +743,11 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer,
                     warn_report("tap: open vhost char device failed: %s",
                                 strerror(errno));
                 }
-                return;
+                goto failed;
             }
             if (!g_unix_set_fd_nonblocking(vhostfd, true, NULL)) {
                 error_setg_errno(errp, errno, "Failed to set FD nonblocking");
-                return;
+                goto failed;
             }
         }
         options.opaque = (void *)(uintptr_t)vhostfd;
@@ -760,11 +760,17 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer,
             } else {
                 warn_report(VHOST_NET_INIT_FAILED);
             }
-            return;
+            goto failed;
         }
     } else if (vhostfdname) {
         error_setg(errp, "vhostfd(s)= is not valid without vhost");
+        goto failed;
     }
+
+    return;
+
+failed:
+    qemu_del_net_client(&s->nc);
 }
 
 static int get_fds(char *str, char *fds[], int max)