FIP v3 implementation

[superna9999]

This implements FIP v3 creation:

• add clear TOC with a 0x10 offset and a final sh256 hash
• add "DATA" entries with data in the TOC buffer
• add DDR Firmwares needed for G12A/G12B/SM1 BootROM

Tested on VIM3L (SM1) & VIM (g12b), and no regression on V2 FIP generation (tested with libretech-cc with make image UBOOT=)

[angerman]

Nice. I haven't had a chance to test this yet, but I'd be delighted to retire https://github.com/angerman/meson64-tools for this.

[repk]

Sorry for the delay, I thought this was still in WIP state. Thanks a lot for that