pgsql: Defend against bad trigger definitions in contrib/lo's lo_manage

Defend against bad trigger definitions in contrib/lo's lo_manage() trigger.

This function formerly crashed if called as a statement-level trigger,
or if a column-name argument wasn't given.

In passing, add the trigger name to all error messages from the function.
(None of them are expected cases, so this shouldn't pose any compatibility
risk.)

Marc Cousin, reviewed by Sawada Masahiko

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/64d15e424091d8fd2c882356ee4bf07cfc5ff69d

Modified Files
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contrib/lo/lo.c |   14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)