Fix SDL_GPUShaderFormat flag values

Fixes #10797

include/SDL3/SDL_gpu.h

@@ -587,12 +587,12 @@ typedef enum SDL_GPUShaderStage
 typedef Uint32 SDL_GPUShaderFormat;
 
 #define SDL_GPU_SHADERFORMAT_INVALID  0
-#define SDL_GPU_SHADERFORMAT_PRIVATE  (1u << 1) /**< Shaders for NDA'd platforms. */
-#define SDL_GPU_SHADERFORMAT_SPIRV    (1u << 2) /**< SPIR-V shaders for Vulkan. */
-#define SDL_GPU_SHADERFORMAT_DXBC     (1u << 3) /**< DXBC SM5_0 shaders for D3D11. */
-#define SDL_GPU_SHADERFORMAT_DXIL     (1u << 4) /**< DXIL shaders for D3D12. */
-#define SDL_GPU_SHADERFORMAT_MSL      (1u << 5) /**< MSL shaders for Metal. */
-#define SDL_GPU_SHADERFORMAT_METALLIB (1u << 6) /**< Precompiled metallib shaders for Metal. */
+#define SDL_GPU_SHADERFORMAT_PRIVATE  (1u << 0) /**< Shaders for NDA'd platforms. */
+#define SDL_GPU_SHADERFORMAT_SPIRV    (1u << 1) /**< SPIR-V shaders for Vulkan. */
+#define SDL_GPU_SHADERFORMAT_DXBC     (1u << 2) /**< DXBC SM5_0 shaders for D3D11. */
+#define SDL_GPU_SHADERFORMAT_DXIL     (1u << 3) /**< DXIL shaders for D3D12. */
+#define SDL_GPU_SHADERFORMAT_MSL      (1u << 4) /**< MSL shaders for Metal. */
+#define SDL_GPU_SHADERFORMAT_METALLIB (1u << 5) /**< Precompiled metallib shaders for Metal. */
 
 /**
  * Specifies the format of a vertex attribute.