doc: Fix incorrect UUID index entry in function documentation.

Previously, the UUID functions documentation defined the "UUID" index entry
to link to the UUID data type page, even though that entry already exists there.
Instead, the UUID functions page should define its own index entry linking
to itself.

This commit updates the UUID index entry in the UUID functions documentation
to point to the correct section, improving navigation and avoiding duplication.

Back-patch to all supported versions.

Author: Fujii Masao 
Reviewed-by: Masahiko Sawada 
Reviewed-by: Daniel Gustafsson 
Discussion: https://postgr.es/m/f33e0493-5773-4296-87c5-7ce459054cfe@oss.nttdata.com
Backpatch-through: 13

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index a6d79765c1a73bcea14ee4ee2a370f1da1e8d4aa..224d4fe5a9f95c8273edacc92a48b721806be6a1 100644 (file)
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -14384,7 +14384,7 @@ CREATE TYPE rainbow AS ENUM ('red', 'orange', 'yellow', 'green', 'blue', 'purple
  
   UUID Functions
 
-  datatype-uuid">
+  functions-uuid">
    UUID
    generating