Remove DISABLE_TWINDDLING_ROUTINE directive

The `DISABLE_TWINDDLING_ROUTINE` preprocessor directive and its associated code have been removed from `PvrtcDecoder.cs`. This directive was previously used to conditionally disable the twiddling routine with a simplified calculation.

The removal simplifies the codebase by eliminating conditional logic, ensuring the twiddling routine is always executed. The `#else` block containing the twiddling logic remains intact, and the `#endif` directive has been removed as it is no longer necessary.

Author: ds5678

AssetRipper.TextureDecoder/Pvrtc/PvrtcDecoder.cs

@@ -1,4 +1,3 @@
-//#define DISABLE_TWINDDLING_ROUTINE
 #define ASSUME_IMAGE_TILING
 
 using AssetRipper.TextureDecoder.Rgb;
@@ -180,10 +179,6 @@ private static uint TwiddleUV(uint ySize, uint xSize, uint yPos, uint xPos)
 				maxValue = yPos;
 			}
 
-#if DISABLE_TWINDDLING_ROUTINE
-			// nasty hack to disable twiddling
-			return (yPos * xSize + xPos);
-#else
 			// step through all the bits in the "minimum" dimension
 			uint srcBitPos = 1;
 			uint dstBitPos = 1;
@@ -211,7 +206,6 @@ private static uint TwiddleUV(uint ySize, uint xSize, uint yPos, uint xPos)
 			maxValue >>= shiftCount;
 			twiddled |= (maxValue << (2 * shiftCount));
 			return twiddled;
-#endif
 		}
 
 		/// <summary>