pgsql: docs: adjust simpler language for NULL return from ANY/ALL

docs: adjust simpler language for NULL return from ANY/ALL

Adjustment to commit 8610c973ddf1cbf0befc1369d2cf0d56c0efcd0a.

Reported-by: Tom Lane

Discussion: /messages/by-id/17406.1541168421@sss.pgh.pa.us

Backpatch-through: 9.3

Branch
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REL9_5_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/d403ed2acd35c326df7e20f91ce679f2c2e7ad1a

Modified Files
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doc/src/sgml/func.sgml | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)