Remove unnecessary "DISTINCT" in psql's queries for \dAc and \dAf.

Remove unnecessary "DISTINCT" in psql's queries for \dAc and \dAf.

A moment's examination of these queries is sufficient to see that
they do not produce duplicate rows, unless perhaps there's
catalog corruption.  Using DISTINCT anyway is inefficient and
confusing; moreover it sets a poor example for anyone who
refers to psql -E output to see how to query the catalogs.