pgsql: Replace remaining StrNCpy() by strlcpy()

Replace remaining StrNCpy() by strlcpy()

They are equivalent, except that StrNCpy() zero-fills the entire
destination buffer instead of providing just one trailing zero.  For
all but a tiny number of callers, that's just overhead rather than
being desirable.

Remove StrNCpy() as it is now unused.

In some cases, namestrcpy() is the more appropriate function to use.
While we're here, simplify the API of namestrcpy(): Remove the return
value, don't check for NULL input.  Nothing was using that anyway.
Also, remove a few unused name-related functions.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/44f5e198-36f6-6cdb-7fa9-60e34784daae%402ndquadrant.com

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/1784f278a63866cc144fcd0a2127cadba6a2b7f8

Modified Files
--------------
contrib/pgcrypto/crypt-des.c                       |  2 +-
src/backend/access/transam/slru.c                  |  2 +-
src/backend/access/transam/xlogarchive.c           |  2 +-
src/backend/catalog/pg_constraint.c                |  2 +-
src/backend/commands/indexcmds.c                   |  2 +-
src/backend/commands/statscmds.c                   |  2 +-
src/backend/commands/tablecmds.c                   |  2 +-
src/backend/postmaster/pgstat.c                    |  2 +-
src/backend/replication/logical/logical.c          | 11 ++++-
src/backend/replication/slot.c                     |  2 +-
src/backend/utils/adt/formatting.c                 |  8 ++--
src/backend/utils/adt/name.c                       | 48 ++--------------------
src/backend/utils/adt/pg_locale.c                  |  9 ----
src/backend/utils/adt/ruleutils.c                  |  2 +-
src/common/exec.c                                  |  4 +-
src/include/c.h                                    | 29 -------------
src/include/utils/builtins.h                       |  3 +-
src/interfaces/ecpg/pgtypeslib/dt_common.c         |  4 +-
src/interfaces/ecpg/test/pg_regress_ecpg.c         |  2 +-
.../ssl_passphrase_callback/ssl_passphrase_func.c  |  2 +-
20 files changed, 34 insertions(+), 106 deletions(-)