pgsql: doc: simplify wording of function error affects

doc: simplify wording of function error affects

Reported-by: bob.henkel@gmail.com

Discussion: /messages/by-id/160324449781.693.8298142858847611071@wrigleys.postgresql.org

Backpatch-through: 9.5

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/7868b6d0d79078b4dc462ea49b3a093d8016f58e

Modified Files
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doc/src/sgml/plpgsql.sgml | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)