pgsql: pg_restore: Provide file name with one failure message

pg_restore: Provide file name with one failure message

Almost all error messages already include file name where relevant, but
this one had been overlooked.  Repair.

Backpatch to 9.5.

Author: Euler Taveira <euler.taveira@2ndquadrant.com>
Discussion: https://postgr.es/m/CAH503wA_VOrcKL_43p9atRejCDYmOZ8MzfK9S6TJrQqBqNeAXA@mail.gmail.com
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/f8635747ee9c07844819075675b2c5c07a7e016e

Modified Files
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src/bin/pg_dump/pg_backup_directory.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)