Allow intermediate scaling step in Sharp Billinear grow more than the…

… final size

Should slightly improve quality when the intermediate step is closer to the next scale factor than a floor would have

GSE/PostProcessor.cs

@@ -86,15 +86,17 @@ private void CalculateScaledRect(in SDL_Rect srcRect, ref SDL_Rect dstRect, bool
 
 		if (integerScaleOnly)
 		{
-			var scaleW = Math.Max(dstWidth / srcWidth, 1);
-			var scaleH = Math.Max(dstHeight / srcHeight, 1);
+			var scaleW = Math.Max((int)Math.Round(dstWidth / (double)srcWidth, MidpointRounding.AwayFromZero), 1);
+			var scaleH = Math.Max((int)Math.Round(dstHeight / (double)srcHeight, MidpointRounding.AwayFromZero), 1);
 			if (config.KeepAspectRatio)
 			{
 				var scale = Math.Min(scaleW, scaleH);
 				scaleW = scale;
 				scaleH = scale;
 			}
 
+			// this can make the dstRect "grow"
+			// but that's fine here, as the intermediate texture will grow accordingly
 			dstWidth = srcWidth * scaleW;
 			dstHeight = srcHeight * scaleH;