[COMMITTERS] pgsql: Remove dead code in nodeGatherMerge.c.

Remove dead code in nodeGatherMerge.c.

Coverity noted that the last line of gather_merge_getnext() was
unreachable, since each arm of the preceding "if" ends in a "return".
Drop it as an oversight.  In passing, improve some nearby comments.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/5d3f7c57ab9c9e2f074ad29d619056570fc5c51e

Modified Files
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src/backend/executor/nodeGatherMerge.c | 25 +++++++++++++------------
1 file changed, 13 insertions(+), 12 deletions(-)