Docs: clarify values for master/standby in gp_segment_configuration
<entry colname="col3"/>
<entry colname="col4">The synchronization status of a segment instance with its mirror
copy. Values are <codeph>s</codeph> (synchronized) or <codeph>n</codeph> (not
- synchronized).</entry>
+ synchronized).<note>This column always shows <codeph>n</codeph> for the master
+ segment and <codeph>s</codeph> for the standby master segment, but these values do
+ not describe the synchronization state for the master segment. Use <xref
+ href="gp_stat_replication.xml#topic1"/> to determine the synchronization state
+ between the master and standby master.</note></entry>
</row>
<row>
<entry colname="col1">
