HID: roccat: fix build failure if built as module

Fix build failure when roccat and roccat-kone are built as modules.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-roccat.h b/drivers/hid/hid-roccat.h
index 40cca5b9..d8aae0c 100644
--- a/drivers/hid/hid-roccat.h
+++ b/drivers/hid/hid-roccat.h
@@ -15,7 +15,7 @@
 #include <linux/hid.h>
 #include <linux/types.h>
 
-#ifdef CONFIG_HID_ROCCAT
+#if defined(CONFIG_HID_ROCCAT) || defined (CONFIG_HID_ROCCAT_MODULE)
 int roccat_connect(struct hid_device *hid);
 void roccat_disconnect(int minor);
 int roccat_report_event(int minor, u8 const *data, int len);