3483/rtx: merged rtx branch (rtx-remix v0.4.1)

This release comes in two variants: default and rtx. If you want to use nvidia's rtx-remix, download the rtx variant.

rtx variant includes:

• remix-bridge nightly: https://github.com/NVIDIAGameWorks/bridge-remix/actions/runs/7835937549
• dxvk-remix nightly: https://github.com/NVIDIAGameWorks/dxvk-remix/actions/runs/7837829106
• all required iw3xo - rtx assets

Changelog:

Added commandline arguments:

• -no_rtx :: disable all rtx modules (useful if you are using a d3d9.dll that is not rtx remix)
• -no_d3d9_check :: active rtx modules even if no d3d9.dll was found (eg: if you are loading remix using asi loader)

Fixes:

• fixed a bug that led to uppercase mod names - fs_game
• playing demos with a mod that has no mod.ff should now work