Fix tag name

Author: drewnoakes

MetadataExtractor/Formats/Exif/ExifDirectoryBase.cs

@@ -895,7 +895,7 @@ protected static void AddExifTagNames(Dictionary<int, string> map)
             map[TagLensModel] = "Lens Model";
             map[TagLensSerialNumber] = "Lens Serial Number";
             map[TagGdalMetadata] = "GDAL Metadata";
-            map[TagGdalNoData] = "GDAL No Data";
+            map[TagGdalNoData] = "GDAL NoData";
             map[TagGamma] = "Gamma";
             map[TagPrintImageMatchingInfo] = "Print Image Matching (PIM) Info";
             map[TagPanasonicTitle] = "Panasonic Title";