pgsql: Fix minor issues in psql's new \dAc and related commands.

Fix minor issues in psql's new \dAc and related commands.

The type-name pattern in \dAc and \dAf was matched only to the actual
pg_type.typname string, which is fairly user-unfriendly in cases where
that is not what's shown to the user by format_type (compare "_int4"
and "integer[]"). Make this code match what \dT does, i.e. match the
pattern against either typname or format_type() output. Also fix its
broken handling of schema-name restrictions. (IOW, make these
processSQLNamePattern calls match \dT's.) While here, adjust
whitespace to make the query a little prettier in -E output, too.

Also improve some inaccuracies and shaky grammar in the related
documentation.

Noted while working on a patch for intarray's opclasses; I wondered
why I couldn't get a match to "integer*" for the input type name.

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/719304a3043d9f60247df371f55236058a7f3caa

Modified Files
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doc/src/sgml/indices.sgml | 9 +++++++++
doc/src/sgml/ref/psql-ref.sgml | 38 ++++++++++++++++++++------------------
src/bin/psql/describe.c | 28 +++++++++++++++++++---------
3 files changed, 48 insertions(+), 27 deletions(-)