pgsql: During parallel pg_dump, free commands from master

During parallel pg_dump, free commands from master

The command strings read by the child processes during parallel
pg_dump, after being read and handled, were not being free'd.
This patch corrects this relatively minor memory leak.

Leak found by the Coverity scanner.

Back patch to 9.3 where parallel pg_dump was introduced.

Branch
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REL9_3_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/8839e7362c68470f8db66acdfa60b95a1c5312cf

Modified Files
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src/bin/pg_dump/parallel.c |    3 +++
1 file changed, 3 insertions(+)