pgsql: Properly clear the verbose output of pg_basebackup

Properly clear the verbose output of pg_basebackup

Don't leave partial filename information on the last status or
dangling characters if the previous filename was longer than
the current one.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/4a0014806d909bbb490f568af0b8f1ede06149ed

Modified Files
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src/bin/pg_basebackup/pg_basebackup.c |   25 +++++++++++++++++++------
1 files changed, 19 insertions(+), 6 deletions(-)