pgsql: Fix misc typos.

Fix misc typos.

Oskari Saarenmaa. Backpatch to stable branches where applicable.

Branch
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REL9_0_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/567acf259b25961e473d48e288ec3c98d7008763

Modified Files
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contrib/btree_gist/btree_ts.c         |    2 +-
contrib/btree_gist/btree_utils_var.c  |    2 +-
src/backend/access/common/heaptuple.c |    2 +-
src/backend/access/gin/ginfast.c      |    4 ++--
src/backend/optimizer/path/costsize.c |    2 +-
5 files changed, 6 insertions(+), 6 deletions(-)