pgsql: Rename updateNodeLink to spgUpdateNodeLink.

Rename updateNodeLink to spgUpdateNodeLink.

On reflection, the original name seems way too generic for a global
symbol.  A quick check shows this is the only exported function name
in SP-GiST that doesn't begin with "spg" or contain "SpGist", so the
rest of them seem all right.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/8f57b064fdaa682ddea60f5dc27c0a5d5fcbffab

Modified Files
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src/backend/access/spgist/spgdoinsert.c |   10 +++++-----
src/backend/access/spgist/spgxlog.c     |   20 ++++++++++----------
src/include/access/spgist_private.h     |    4 ++--
3 files changed, 17 insertions(+), 17 deletions(-)