pgsql: Fix bogus CALLED_AS_TRIGGER() defenses.

Fix bogus CALLED_AS_TRIGGER() defenses.

contrib/lo's lo_manage() thought it could use
trigdata->tg_trigger->tgname in its error message about
not being called as a trigger. That naturally led to a core dump.

unique_key_recheck() figured it could Assert that fcinfo->context
is a TriggerData node in advance of having checked that it's
being called as a trigger. That's harmless in production builds,
and perhaps not that easy to reach in any case, but it's logically
wrong.

The first of these per bug #16340 from William Crowell;
the second from manual inspection of other CALLED_AS_TRIGGER
call sites.

Back-patch the lo.c change to all supported branches, the
other to v10 where the thinko crept in.

Discussion: https://postgr.es/m/[email protected]

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a9f821f48893308fbb5533a1b722c233eaa2d603

Modified Files
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contrib/lo/lo.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)