pgsql: Rephrase some not-supported error messages in pg_hba.conf proces

Rephrase some not-supported error messages in pg_hba.conf processing.

In a couple of places we said "not supported on this platform" for cases
that aren't really platform-specific, but could depend on configuration
options such as --with-openssl. Use "not supported by this build" instead,
as that doesn't convey the impression that you can't fix it without moving
to another OS; that's also more consistent with the wording used for an
identical error case in guc.c.

No back-patch, as the clarity gain is small enough to not be worth
burdening translators with back-branch changes.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/71e7083532d8f6ad0cf345c3cc534b0307e816a8

Modified Files
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src/backend/libpq/hba.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)