pgsql: strnlen() is now required

strnlen() is now required

Remove all configure checks and workarounds for strnlen() missing.  It
is required by POSIX 2008.

Reviewed-by: Jelte Fennema-Nio <postgres@jeltef.nl>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/98ce805c-6103-421b-adc3-fcf8f3dddbe3%40eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/5e7abdac99136c63850a23c0dfdec24d81f503f1

Modified Files
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configure                  | 23 -----------------------
configure.ac               |  3 +--
meson.build                |  2 --
src/include/pg_config.h.in |  7 -------
src/include/port.h         |  4 ----
src/port/meson.build       |  1 -
src/port/strnlen.c         | 33 ---------------------------------
7 files changed, 1 insertion(+), 72 deletions(-)