Fixed: Don't load grayscale textures as alpha

--HG--
branch : develop

code/nel/tools/3d/panoply_maker/panoply_maker.cpp

@@ -656,6 +656,9 @@ static void BuildColoredVersionForOneBitmap(const CBuildInfo &bi, const std::str
 		{
 			if (is.open(fullInputBitmapPath))
 			{
+				// 8 bits textures are grayscale
+				srcBitmap.loadGrayscaleAsAlpha(false);
+
 				depth = srcBitmap.load(is);
 				is.close();