fix check ddi version for < rs3 (#1169)

tools/dxexp/dxexp.cpp

@@ -78,6 +78,10 @@ typedef struct D3D12_FEATURE_DATA_D3D12_OPTIONS3
 } 	D3D12_FEATURE_DATA_D3D12_OPTIONS3;
 #endif
 
+#ifndef NTDDI_WIN10_RS3
+#define NTDDI_WIN10_RS3 0x0A000004  
+#endif
+
 #if WDK_NTDDI_VERSION <= NTDDI_WIN10_RS3
 #define D3D_SHADER_MODEL_6_2 ((D3D_SHADER_MODEL)0x62)
 #define D3D12_FEATURE_D3D12_OPTIONS4 ((D3D12_FEATURE)23)