[S] Change in libgfxinit[main]: gfxtest: Fix out-of-order components, permanently

[Angel Pons (Code Review)]

Attention is currently required from: Elyes Haouas.

Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/libgfxinit/+/81854?usp=email )

Change subject: gfxtest: Fix out-of-order components, permanently
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Patch Set 1:

(1 comment)

File gfxtest/hw-gfx-gma-gfx_test.adb:

https://review.coreboot.org/c/libgfxinit/+/81854/comment/1ee662d4_31a9a772 :
PS1, Line 54: Blue  : Byte;
            :       Green : Byte;
            :       Red   : Byte;
> I would keep using the RGB order  […]

Problem is, this record defines the byte ordering for the hardware. This patch should allow the RGB-to-BGR swizzling to be done at compile time, so that there's no extra runtime cost.

If I were to use RGB ordering here, then `Pixel_To_Word` would have to unscramble the pixel, which is harder to work with.