ar71xx: add naive support for DIR-825

targets/ar71xx-generic

@@ -103,6 +103,10 @@ device('d-link-dir-825-rev-b1', 'dir-825-b1', {
 	class = 'tiny', -- Only 6M of usable Firmware space
 })
 
+device('d-link-dir-825-rev-c1', 'dir-825-c1', {
+	profile = 'DIR825C1'
+})
+
 
 -- GL.iNet