pgsql: Remove obsolete global database_ctype_is_c.

Remove obsolete global database_ctype_is_c.

Now that tsearch uses the database default locale, there's no need to
track the database CTYPE separately.

Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/0151ad01239e2cc7b3139644358cf8f7b9622ff7.camel@j-davis.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/844385d12e7515f3461e53728f0a9358bc35b6a5

Modified Files
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src/backend/utils/adt/pg_locale.c | 3 ---
src/backend/utils/init/postinit.c | 4 ----
src/include/utils/pg_locale.h     | 3 ---
3 files changed, 10 deletions(-)