Thai character sets are not recognized correctly

Thai locales are not recognized correctly.

ISO 8859-11 exists as an alias to TIS-620 in corelib/codecs/qsimplecodec.cpp, but usually ISO charsets are written as ISO-8859-11.
Requesting to add the dash between iso and the number.

IBM codepage 874 exists under the aliases CP874 and IBM874, but windows-874 is missing, although it seems to be pretty common:
http://w3techs.com/technologies/details/en-windows874/all/all

iana says this about windows-874:

http://www.iana.org/assignments/charset-reg/windows-874

"This charset is also known as Windows Code Page 874, DOS-874,
or cp874 for short; these are NOT aliases." Not sure what to make of the "not alias" part though. Requesting to add windows-874 as an alias to IBM-874.