This is the first set of patches to move targa decoding out of WIC and into d3dx9. The eventual goal is to add support for saving targa files.
I've pushed a branch with the rest of the patches for decoding the image [here](https://gitlab.winehq.org/cmcadams/wine/-/tree/WIP/d3dx9-targa-decode-v2) if extra context would help. I split this into two parts to make review a little less overwhelming. :)