[Nokia N-Gage] Re-enable FPS counter, fix link in README.

- Re-enable FPS counter, which is hidden by default anyway - but essential while working on an actual project.
- Fix link in the platform's README.
- Re-order list of supported platforms (alphabetical order to maintain consistency).

docs/README-platforms.md

@@ -12,6 +12,7 @@
 - [NetBSD](README-bsd.md)
 - [Nintendo Switch](README-switch.md)
 - [Nintendo 3DS](README-n3ds.md)
+- [Nokia N-Gage](README-ngage.md)]
 - [OpenBSD](README-bsd.md)
 - [PlayStation 2](README-ps2.md)
 - [PlayStation 4](README-ps4.md)
@@ -24,7 +25,6 @@
 - [Windows](README-windows.md)
 - [Windows GDK](README-gdk.md)
 - [Xbox](README-gdk.md)
-- [Nokia N-Gage](README-ngage.md)
 
 ## Unsupported Platforms