Reword 'simple comparison' => 'inequality' in pgtrgm.sgml

Discussion: https://postgr.es/m/CAMkU%3D1zxfA8_MGBW6sJMj54p8nPoe4bMb5LoG-rMYZVPq4j08Q%40mail.gmail.com
Author: Jeff Janes

doc/src/sgml/pgtrgm.sgml

@@ -421,7 +421,7 @@
    trigram-based index searches for <literal>LIKE</literal>, <literal>ILIKE</literal>,
    <literal>~</literal> and <literal>~*</literal> queries.  Beginning in
    <productname>PostgreSQL</productname> 14, these indexes also support
-   the equality operator (simple comparison operators are not supported).
+   the equality operator (inequality operators are not supported).
    Note that those indexes may not be as efficient as regular B-tree indexes
    for equality operator.
   </para>