Add PsyZ support

[Xeeynamo]

Highly Experimental effort with the minimum amount of changes required to allow the core components of the game to run in a portable way.

This should serve as a greater effort to debug and experiment with the code without having to rely on an emulator.

# run this at least once
git submodule update --init --recursive

# to test it
make pc && ./build/pc/ff7

Key bindings:

• D: Circle / Confirm
• X: Cross / Back
• S: Triangle / Menu

Instructions:

• In GameMain comment out func_800A0030 to skip the SCEA logo
• The SquareSoft logo is unimplemented and the screen will be black. You need to press D to skip and go to the Title Screen
• TITLE SysMenuHandleButtons is unimplemented, pressing D will always go to NEW GAME and hang.
• The "finger" cursor is black due to an unknown rendering bug. To make it visible, go to SysMenuDrawCursor and change the second parameter of GetTPage from 2 to 1
• To access a memory card save, extract the 0x2000 byte save data as bu00/BASCUS-94163FF7-S01 in the project's root

To select CONTINUE? on the title screen without SysMenuHandleButtons implemented, you'd need to force the CONTINUE? option with the following change:

#ifndef VERSION_PC
                    func_801D2B58(0xD0);
                    D_801E3698 = 1;
                    D_801E3D54 = 2;
                    break;
#endif