pgsql: psql: Clean up terminology in \dAp command

psql: Clean up terminology in \dAp command

The preferred terminology has been support "function", not procedure,
for some time, so change that over. The command stays \dAp, since
\dAf is already something else.

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/f5067049cde38cd0d6333a5e3bf1bed8d99e6f44

Modified Files
--------------
doc/src/sgml/ref/psql-ref.sgml | 2 +-
src/bin/psql/command.c | 2 +-
src/bin/psql/describe.c | 10 +++++-----
src/bin/psql/describe.h | 4 ++--
src/bin/psql/help.c | 2 +-
src/test/regress/expected/psql.out | 8 ++++----
6 files changed, 14 insertions(+), 14 deletions(-)