Update XMP IPTC tags to 2021.1 standard

Changes:
1. Add/update tags.
2. According to the standard, several tags in
   `Xmp.iptc.<property>` and `Xmp.iptcExt.<property>`, had been
   wrongly added, as they only exist as part of a struct used by a
   tag. The incorrect tags have been marked as deprecated in the
   label and description.
3. Update existing test with translated output.

Ref: [IPTC Photo Metadata Standard 2021.1](https://www.iptc.org/std/photometadata/specification/IPTC-PhotoMetadata-2021.1.html)

src/tags_int.hpp

@@ -345,6 +345,32 @@ namespace Exiv2 {
 //! Shortcut for the printTagVocabulary template which requires typing the array name only once.
 #define EXV_PRINT_VOCABULARY(array) printTagVocabulary<EXV_COUNTOF(array), array>
 
+    template <int N, const TagVocabulary (&array)[N]>
+    std::ostream& printTagVocabularyMulti(std::ostream& os, const Value& value, const ExifData*)
+    {
+        if (value.count() == 0) {
+            os << "(" << value << ")";
+            return os;
+        }
+
+        for (int i=0; i< value.count(); i++) {
+            if (i != 0)
+                os << ", ";
+            const TagVocabulary* td = find(array, value.toString(i));
+            if (td) {
+                os << exvGettext(td->label_);
+            }
+            else {
+                os << "(" << value.toString(i) << ")";
+            }
+        }
+
+        return os;
+    }
+
+//! Shortcut for the printTagVocabularyMulti template which requires typing the array name only once.
+#define EXV_PRINT_VOCABULARY_MULTI(array) printTagVocabularyMulti<EXV_COUNTOF(array), array>
+
 // *****************************************************************************
 // free functions
 

tests/bugfixes/github/test_pr1475_AVIF.py

@@ -73,7 +73,7 @@ class pr_1475_exif_xmp_avif(metaclass=system_tests.CaseMeta):
         stderr = [ "" ] * len(commands)
         stdin  = [ "" ] * len(commands)
         stdout = ["""Exif.Image.DateTime                          Ascii      20  2021:02:13 21:19:50
-Xmp.iptcExt.DigitalSourceType                XmpText    61  http://cv.iptc.org/newscodes/digitalsourcetype/digitalCapture
+Xmp.iptcExt.DigitalSourceType                XmpText    61  Digital capture
 Xmp.iptcExt.LocationCreated                  XmpBag      0  
 Xmp.iptcExt.LocationShown                    XmpBag      0  
 Xmp.iptcExt.ArtworkOrObject                  XmpBag      0  
@@ -268,7 +268,7 @@ class pr_1475_metadata2_avif(metaclass=system_tests.CaseMeta):
         stderr = [ "" ] * len(commands)
         stdin  = [ "" ] * len(commands)
         stdout = ["""Exif.Image.DateTime                          Ascii      20  2021:02:13 21:25:32
-Xmp.iptcExt.DigitalSourceType                XmpText    61  http://cv.iptc.org/newscodes/digitalsourcetype/digitalCapture
+Xmp.iptcExt.DigitalSourceType                XmpText    61  Digital capture
 Xmp.iptcExt.LocationCreated                  XmpBag      0  
 Xmp.iptcExt.LocationShown                    XmpBag      0  
 Xmp.iptcExt.ArtworkOrObject                  XmpBag      0