pgsql: doc: Change statistics function xref to the right target

doc: Change statistics function xref to the right target

Commit 7d3b7011b added a link to the statistics functions, which at the
time were anchored under the section for statistics views. aebe989477a
added a separate section for statistics functions, but the link was not
updated to point to the new anchor. Fix by changing the xref.

Backpatch to all supported branches.

Author: Peter Smith <peter.b.smith@fujitsu.com>
Discussion: /messages/by-id/CAHut+Ptr0jKzNNtWnssLq+3jNhbyaBseqf6NPrWHk08mQFRoTg@mail.gmail.com
Backpatch-through: 11

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/750beed859f0ea4f87f2812177755ef4234dfb80

Modified Files
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doc/src/sgml/func.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)