[PATCH] Fix docs to JOHAB encoding on server side

Lars Kanis <lars@greiz-reinsdorf.de> writes:

The current documentation is inconsistent about the JOHAB character encoding on server side. While the first table says that it is not possible to use JOHAB on server side, it is still listed in table 23.2 as a server character set:
https://www.postgresql.org/docs/devel/static/multibyte.html#MULTIBYTE-CHARSET-SUPPORTED

Hm, yeah. Probably this is because JOHAB was first installed as being
a server-allowed encoding, and it was only later we realized that wasn't
OK. This table must've been missed while changing it.

Cross-checking the other entries, I notice SHIFT_JIS_2004 is also not
listed in that table ... we've been a little sloppy there.

Thanks for noticing!

regards, tom lane