Doc: Fix contrib/amcheck tip.
Fixes an oversight in commit
@@ -168,7 +168,7 @@ ORDER BY c.relpages DESC LIMIT 10;
</variablelist>
<tip>
<para>
- <function>bt_index_parent_check</function> and
+ <function>bt_index_check</function> and
<function>bt_index_parent_check</function> both output log
messages about the verification process at
<literal>DEBUG1</literal> and <literal>DEBUG2</literal> severity
