pgsql: Rename GistTranslateStratnum() to GistTranslateCompareType()

Rename GistTranslateStratnum() to GistTranslateCompareType()

Follow up to commit 630f9a43cec.  The previous name had become
confusing, because it doesn't actually translate a strategy number but
a CompareType into a strategy number.  We might add the inverse at
some point, which would then probably be called something like
GistTranslateStratnum.

Reviewed-by: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a5709b5bb293a554913c4b1f6a9c58d1915ba3f7

Modified Files
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src/backend/access/gist/gistutil.c     | 2 +-
src/backend/commands/indexcmds.c       | 2 +-
src/backend/commands/tablecmds.c       | 4 ++--
src/backend/executor/execReplication.c | 2 +-
src/include/access/gist.h              | 2 +-
5 files changed, 6 insertions(+), 6 deletions(-)