pgsql: Use appendStringInfoString/Char et al where appropriate.

Use appendStringInfoString/Char et al where appropriate.

Patch by David Rowley. Backpatch to 9.5, as some of the calls were new in
9.5, and keeping the code in sync with master makes future backpatching
easier.

Branch
------
master

Details
-------
http://git.postgresql.org/pg/commitdiff/f92d6a540ac443f85f0929b284edff67da14687a

Modified Files
--------------
contrib/postgres_fdw/postgres_fdw.c | 2 +-
src/backend/access/rmgrdesc/gindesc.c | 4 ++--
src/backend/access/rmgrdesc/spgdesc.c | 10 +++++-----
src/backend/access/rmgrdesc/xactdesc.c | 2 +-
src/backend/access/transam/xlog.c | 4 ++--
src/backend/lib/pairingheap.c | 2 +-
src/backend/utils/adt/ruleutils.c | 2 +-
src/backend/utils/adt/xml.c | 6 +++---
src/bin/pg_basebackup/pg_basebackup.c | 2 +-
src/bin/pg_dump/pg_backup_archiver.c | 2 +-
src/bin/pg_dump/pg_dump.c | 6 +++---
src/bin/psql/describe.c | 8 ++++----
src/bin/scripts/clusterdb.c | 2 +-
src/bin/scripts/createdb.c | 4 ++--
src/bin/scripts/createuser.c | 2 +-
src/bin/scripts/reindexdb.c | 2 +-
src/bin/scripts/vacuumdb.c | 4 ++--
17 files changed, 32 insertions(+), 32 deletions(-)