Sync SDL3 wiki -> header

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include/SDL3/SDL_gpu.h

@@ -2197,11 +2197,12 @@ extern SDL_DECLSPEC SDL_GPUSampler *SDLCALL SDL_CreateGPUSampler(
  *   [[stage_in]] attribute which will automatically use the vertex input
  *   information from the SDL_GPUGraphicsPipeline.
  *
- * Shader semantics do not matter in D3D12 and for ease of use the SDL
- * implementation assumes that they will all be TEXCOORD. If you are using
- * HLSL as the shader source language, your vertex semantics should start at
- * TEXCOORD0 and increment like so: TEXCOORD1, TEXCOORD2, etc. If you wish to
- * change the semantic prefix to something other than TEXCOORD you can use
+ * Shader semantics other than system-value semantics do not matter in D3D12
+ * and for ease of use the SDL implementation assumes that non system-value
+ * semantics will all be TEXCOORD. If you are using HLSL as the shader source
+ * language, your vertex semantics should start at TEXCOORD0 and increment
+ * like so: TEXCOORD1, TEXCOORD2, etc. If you wish to change the semantic
+ * prefix to something other than TEXCOORD you can use
  * SDL_PROP_GPU_DEVICE_CREATE_D3D12_SEMANTIC_NAME_STRING with
  * SDL_CreateGPUDeviceWithProperties().
  *