usb_kbd: fix usb_kbd_deregister when DEVICE_DEREGISTER not enable

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Remy Böhmer <linux@bohmer.net>
diff --git a/common/usb_kbd.c b/common/usb_kbd.c
index cf14560..89e6ee7 100644
--- a/common/usb_kbd.c
+++ b/common/usb_kbd.c
@@ -211,7 +211,11 @@
 /* deregistering the keyboard */
 int usb_kbd_deregister(void)
 {
+#ifdef CONFIG_SYS_DEVICE_DEREGISTER
 	return device_deregister(DEVNAME);
+#else
+	return 1;
+#endif
 }
 
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