ngp: settings must be done each time

[jotego]

commit: d49204f

The NVRAM contents do not seem to get created or loaded correctly, so the settings menu must be dealt with each time.

[jotego]

The NVRAM file is all zeroes in MiSTer. APocket does not create a file at all.

[jotego]

Done some improvements to saving and restoring the state in b73d702. But, this is still not enough. It looks like a custom firmware is needed to prevent the system from overwritting data each time. Booting up from the FF1800 vector is not enough either.

The best solution for users is to power off the NGP, insert a cartridge and then power on again. That bypasses the settings.