pgsql: Remove obsolete defense against strxfrm() bugs.

Remove obsolete defense against strxfrm() bugs.

Old versions of Solaris and illumos had buffer overrun bugs in their
strxfrm() implementations. The bugs were fixed more than a decade ago
and the relevant releases are long out of vendor support. It's time to
remove the defense added by commit be8b06c3.

Reviewed-by: Nathan Bossart <nathandbossart(at)gmail(dot)com>
Reviewed-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Discussion: https://postgr.es/m/CA+hUKGJ-ZPJwKHVLbqye92-ZXeLoCHu5wJL6L6HhNP7FkJ=meA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/7d3d72b55edd1b7552a9a358991555994efab0e9

Modified Files
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src/backend/main/main.c | 2 --
src/backend/utils/adt/pg_locale.c | 58 ---------------------------------------
src/backend/utils/init/postinit.c | 2 --
src/include/utils/pg_locale.h | 1 -
4 files changed, 63 deletions(-)