SW: Fix alignedWidth in TextureEncoder

[PatrickFerry]

This was causing issues in Software Renderer.

Attempting to solve https://bugs.dolphin-emu.org/issues/11487

[shuffle2]

for which values of width, sBlkSize do you see this change producing different result from Common::AlignUp? That there is any difference suggests a kinda catastrophic bug in AlignUp

[shuffle2]

It also seems like sBlkSize and tBlkSize are u16s that only store a power of 2 value, so the type of the args to SetSpans should be u16, and ENCODE_LOOP_BLOCKS should be changed to make t/s u32s?

[shuffle2]

Oh, I missed that your replacement is (value + align) & ~(align-1) instead of the typical (value + align - 1) & ~(align-1). I guess this is because width is 1 less than the number of pixels of width

[PatrickFerry]

I would be happy for someone else to take over since I'm not sure what the alignedWidth value should be in this case.

width = 388
sBlkSize = 4

(Broken)
Common::AlignUp(width, sBlkSize) = 388

(Seems to work)
Common::AlignUp(width+1, sBlkSize) = 392

(Seems to work and was how this written before d7dc854)
(width + sBlkSize) & (~(sBlkSize - 1)) = 392

[shuffle2]

Yea I think this PR is fine as-is, just took me a while to realize that d7dc854 caused that comment (width is 1 less than the number of pixels of width) to go out of sync with what the code was actually doing. (...right? 🙃)

[PatrickFerry]

Rewritten with alignup to align up to next multiple given that width is one more like the comment suggests

Common::AlignUp(width+1, sBlkSize);

[leoetlino]

Whoops, my bad 😅