Incorrect affine transformations in Wario Land 4 about rustboyadvance-ng HOT 4 CLOSED

@xTibor

https://github.com/michelhe/rustboyadvance-ng/blob/master/rustboyadvance-core/src/iodev.rs#L154

Removing these if-checks for all BG2-3X-Y registers solves this glitch (tested for Wario and sbb_aff.gba)

I've included this check because of the following line in GBATek:

Caution: Writing to a reference point register by software outside of the Vblank period does immediately copy the new value to the corresponding internal register, that means: in the current frame, the new value specifies the origin of the scanline (instead of the topmost scanline).

http://problemkaputt.de/gbatek.htm#lcdiobgrotationscaling

Too tired to continue now, but probably will sort it out tomorrow, might have interpreted this edge-case incorrectly.

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This off-center rotation is also reproducible with the sbb_aff.gba TONC demo (L+R keys) but not as severe as the Wario one.

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@xTibor Good catch, I'll look into it.

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I suspect that I'm not updating the BGX/BGY reference points in the right phase of the PPU state machine.

https://github.com/michelhe/rustboyadvance-ng/blob/master/rustboyadvance-core/src/gpu/mod.rs#L400

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