pgsql: Adjust ExplainOneQuery_hook_type to take a DestReceiver argument

Adjust ExplainOneQuery_hook_type to take a DestReceiver argument.

The materialized views patch adjusted ExplainOneQuery to take an
additional DestReceiver argument, but failed to add a matching
argument to the definition of ExplainOneQuery_hook.  This is a
problem for users of the hook that want to call ExplainOnePlan.
Fix by adding the missing argument.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/0bf42a5f3b62cde41cb366d3442585429c6d9c50

Modified Files
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src/backend/commands/explain.c |    2 +-
src/include/commands/explain.h |    1 +
2 files changed, 2 insertions(+), 1 deletions(-)