rsx/qt: Move blit engine upscaling option to debug settings

[kd-11]

Followup to #19013
The setting was present for debugging. We need to remove it long term, so I am making it a debug setting for now.

[kd-11]

This PR is for testing purposes, to determine how useful the option is and whether default should be on or off.
@digant73 @woj1993 @ShadowH69 who were assisting with testing the previous PR.

[digant73]

R3 is broken when aiming since 0.0.42-19872 (#19013).
Below a video with wiki + WRCB + RSX Memory Tiling

https://mega.nz/file/m2IHFRZQ#xWFFvdueODs2hxxRZZds4O3fy1H8lXVCN0kDQj61gdw

EDIT:

• Rage ([BLUS30485] RAGE - Graphical Bugs #17931) seems fixed with Allow Host GPU (or ATS) enabled
• The Evil Within (The Evil Within - Top area not rendering correctly #17865) already confirmed as fixed. Allow Host GPU (or ATS) is required to reduce flickering textures
• Bioshock 2 has still green water when using odd values of RS (e.g. 250%). Also performance are better disabling Blit Engine Upscaling

[digant73]

since #19013 fire seems ok in split/second with any RS

[kd-11]

R3 is broken when aiming since 0.0.42-19872 (#19013). Below a video with wiki + WRCB + RSX Memory Tiling

https://mega.nz/file/m2IHFRZQ#xWFFvdueODs2hxxRZZds4O3fy1H8lXVCN0kDQj61gdw

I did test this and it's a missing barrier somewhere. Even using different drivers on the same hardware has different output that shows a GPU-side race condition, likely something pre-existing but annoying for sure.