Btrfs ExtentData class issue should be fixed

[MikeGratsas]

Please modify the code of ReadFrom method in DiscUtils.Btrfs/Base/Items/ExtentData.cs file as follows:

            if (Type == ExtentDataType.Inline)
            {
                InlineData = EndianUtilities.ToByteArray(buffer, offset + 0x15, buffer.Length - (offset + 0x15));
                LogicalSize = DecodedSize;
            }

Without the mentioned correction the LogicalSize = 0 for inline extents and the uncompressed data is empty as a result.