pgsql: Typo fixes.

Typo fixes.

expect -> except, noted by Andrew Dunstan. Also, "cannot" seems more
readable here than "can not", per David Wheeler.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/bf82013631e32436c9abb23fee8be0a4ce46b3dd

Modified Files
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doc/src/sgml/func.sgml | 16 ++++++++--------
1 files changed, 8 insertions(+), 8 deletions(-)