Incorrect grammar on ALTER EVENT TRIGGER

The ALTER EVENT TRIGGER ..  page has an extra TRIGGER in the parameters section
for ENABLE/DISABLE parameters which isn't supported in the grammar:

	https://www.postgresql.org/docs/devel/sql-altereventtrigger.html

postgres=# alter event trigger on_login_trigger disable trigger;
ERROR:  syntax error at or near "trigger"
LINE 1: alter event trigger on_login_trigger disable trigger;
                                                     ^
postgres=# alter event trigger on_login_trigger enable trigger;
ERROR:  syntax error at or near "trigger"
LINE 1: alter event trigger on_login_trigger enable trigger;
                                                    ^
postgres=# alter event trigger on_login_trigger enable always trigger;
ERROR:  syntax error at or near "trigger"
LINE 1: alter event trigger on_login_trigger enable always trigger;
                                                           ^
The attached trivial patch removes the extra keyword, which needs to be
backpatched all the way down.

--
Daniel Gustafsson