Removed the vi format comments from the source

Vim users can use the [editorconfig plugin](https://github.com/editorconfig/editorconfig-vim) to automatically set tab spacing for the SDL coding style.

Fixes https://github.com/libsdl-org/SDL/issues/6903

src/render/SDL_d3dmath.c

@@ -130,5 +130,3 @@ Float4X4 MatrixRotationZ(float r)
 }
 
 #endif /* (SDL_VIDEO_RENDER_D3D || SDL_VIDEO_RENDER_D3D11 || SDL_VIDEO_RENDER_D3D12) && !SDL_RENDER_DISABLED */
-
-/* vi: set ts=4 sw=4 expandtab: */