Move clearing of self-aliases upstream to QLocaleXmlWriter

The duplicate entries just bulked up the intermediate file.
Makes no change to generated data.

Task-number: QTBUG-115158
Change-Id: I6dc0d1f79f8dcf2e46264c6f9d1ae06ff4c91394
Reviewed-by: Mate Barany <mate.barany@qt.io>

util/locale_database/qlocalexml.py

@@ -350,6 +350,8 @@ class QLocaleXmlWriter (object):
         # iana is a single IANA ID
         # name has the same form, but has been made redundant
         for name, iana in sorted(alias.items()):
+            if name == iana:
+                continue
             self.__openTag('zoneAlias')
             self.inTag('alias', name)
             self.inTag('iana', iana)

util/locale_database/qlocalexml2cpp.py

@@ -212,9 +212,9 @@ class TimeZoneDataWriter (LocaleSourceEditor):
         out('// Alias ID Index, Alias ID Index\n')
         out('static constexpr AliasData aliasMappingTable[] = {\n')
         for name, iana in pairs: # They're ready-sorted
-            if name != iana:
-                out(f'    {{ {store(name):6d},{store(iana):6d} }},'
-                    f' // {name} -> {iana}\n')
+            assert name != iana, (alias, iana) # Filtered out in QLocaleXmlWriter
+            out(f'    {{ {store(name):6d},{store(iana):6d} }},'
+                f' // {name} -> {iana}\n')
         out('};\n\n')
 
     def msToIana(self, pairs):