Incompatibility between savestate on cores 32 bit and 64 bit

[gplaysrv]

Savestates generated on Genesis-Plus-GX (Retroarch) 32 bit core are incompatible with savestates generated on the same version of Genesis-Plus-GX (Retroarch) core in its variant 64 bit.

Genesis-Plus-GX last version tested:
1.7.4-5055106

Platforms tested:

• Android 7 (32 bit Arm)
• Android 10 (64 bit Arm)
• Lakka linux (32 bit Arm / Raspberry Pi 3b)
• Arch Linux (AMD64 / x64)

[ekeeke]

See ekeeke#311

This is not fixable without breaking support for existing savestates on either 32-bit or 64-bit platforms so I'd advise living with this limitation until savestate format change is needed again for some more important reason.