fix bug 79276

r=bstell sr=blizzard
add additional charset naem for gb18030
should not impact the build

intl/uconv/src/charsetalias.properties

@@ -91,6 +91,7 @@ big5=Big5
 euc-jp=EUC-JP
 euc-kr=EUC-KR
 gb2312=GB2312
+gb18030=gb18030
 viscii=VISCII
 koi8-r=KOI8-R
 koi8-u=KOI8-U
@@ -301,6 +302,7 @@ x-cp1258=windows-1258
 ##
 windows-874=TIS-620
 ibm874=TIS-620
+tis620.2533=TIS-620
 ##
 ## Aliases for IBM866
 ##