pgsql: Rename pg_dump --no-security-label to --no-security-labels

Rename pg_dump --no-security-label to --no-security-labels

Other similar options also use the plural form.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/c8e0c321194c985a13e7c7e4d3110ac032517350

Modified Files
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doc/src/sgml/ref/pg_dump.sgml        |    2 +-
doc/src/sgml/ref/pg_dumpall.sgml     |    2 +-
doc/src/sgml/ref/pg_restore.sgml     |    2 +-
src/bin/pg_dump/pg_backup.h          |    2 +-
src/bin/pg_dump/pg_backup_archiver.c |    2 +-
src/bin/pg_dump/pg_dump.c            |   18 +++++++++---------
src/bin/pg_dump/pg_dumpall.c         |   10 +++++-----
src/bin/pg_dump/pg_restore.c         |    8 ++++----
8 files changed, 23 insertions(+), 23 deletions(-)