pgsql: Fix object identities for pg_conversion objects

Fix object identities for pg_conversion objects

We were neglecting to schema-qualify them.

Backpatch to 9.3, where object identities were introduced as a concept
by commit f8348ea32ec8.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/0d906798f680b2dd86cbc8d31ba64685aeb12092

Modified Files
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src/backend/catalog/objectaddress.c          |    6 +++++-
src/test/regress/expected/object_address.out |    2 +-
2 files changed, 6 insertions(+), 2 deletions(-)