pgsql: Make use of generic logging in vacuumlo and oid2name

Make use of generic logging in vacuumlo and oid2name

Doing the switch reduces the footprint of "progname" in both utilities
for the messages produced. This also cleans up a couple of
inconsistencies in the message formats.

Author: Michael Paquier
Reviewed-by: Álvaro Herrera, Peter Eisentraut
Discussion: /messages/by-id/20190820012819.GA8326@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/fc8cb94bf451cd810ae5b1c1f90b977277247625

Modified Files
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contrib/oid2name/oid2name.c | 18 ++++++++------
contrib/vacuumlo/vacuumlo.c | 59 ++++++++++++++++++++-------------------------
2 files changed, 36 insertions(+), 41 deletions(-)