Remove all deprecations warnings from existing examples

[0xSmartis]

• Updating controllertest.c to latest joypad API
• Replaced deprecated joypad identifier call with joybus API in microuiN64.c

[rasky]

Thanks!

controllertest.c is designed to verify that we don't break the old controller.c API which is now deprecated. So it must continue using the old deprecated API. To remove warnings during builds, I think the best course of action would be to disable the deprecation warning while building this example, in case you want to attempt this. We should also probably add a comment in the example itself explaining this.

[0xSmartis]

Thank you for the feedback.
I changed the controllertest example back to the Controller API and added a note at the beginning of the code.

I also extended the makefile with the flag CFLAGS += -Wno-deprecated-declarations. This should now only ignore the deprecation warnings but still showing errors when something else breaks.