usb-host: Do not override USB node name

QEMU creates nodes for PCI devices and preserves the node names with
one exception for USB hosts; this fixes it.

Fixes: be9b2fa44c73 ("pci: Use QEMU created PCI device nodes")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Thomas Huth <thuth@redhat.com>
diff --git a/slof/fs/usb/dev-hci.fs b/slof/fs/usb/dev-hci.fs
index 5fb25b8..685280c 100644
--- a/slof/fs/usb/dev-hci.fs
+++ b/slof/fs/usb/dev-hci.fs
@@ -20,7 +20,7 @@
 
 \ Open Firmware Properties
 device-type
-" usb" 2dup device-name
+s" usb"
 
 rot
 VALUE usb_num                           \ controller number