Delete AF_UNIX socket after close

Since version 2.12.0 AF_UNIX socket created for QMP exchange is not
deleted on instance shutdown.

This is due to the fact that function qio_channel_socket_finalize() is
called after qio_channel_socket_close().

Signed-off-by: Pavel Balaev <mail@void.so>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

io/channel-socket.c

@@ -685,8 +685,10 @@ qio_channel_socket_close(QIOChannel *ioc,
                          Error **errp)
 {
     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
+    int rc = 0;
 
     if (sioc->fd != -1) {
+        SocketAddress *addr = socket_local_address(sioc->fd, errp);
 #ifdef WIN32
         WSAEventSelect(sioc->fd, NULL, 0);
 #endif
@@ -697,8 +699,22 @@ qio_channel_socket_close(QIOChannel *ioc,
             return -1;
         }
         sioc->fd = -1;
+
+        if (addr && addr->type == SOCKET_ADDRESS_TYPE_UNIX
+            && addr->u.q_unix.path) {
+            if (unlink(addr->u.q_unix.path) < 0 && errno != ENOENT) {
+                error_setg_errno(errp, errno,
+                                 "Failed to unlink socket %s",
+                                 addr->u.q_unix.path);
+                rc = -1;
+            }
+        }
+
+        if (addr) {
+            qapi_free_SocketAddress(addr);
+        }
     }
-    return 0;
+    return rc;
 }
 
 static int