Docs - update PostGIS version compatibility

gpdb-doc/dita/install_guide/platform-requirements.xml

@@ -336,7 +336,7 @@
               <row class="- topic/row ">
                 <entry colname="col1" class="- topic/entry ">MADlib machine
                   learning<sup>1</sup></entry>
-                <entry colname="col3" class="- topic/entry ">MADlib 1.16, 1.17</entry>
+                <entry colname="col3" class="- topic/entry ">MADlib 1.17, 1.16</entry>
               </row>
               <row>
                 <entry>PL/Java</entry>
@@ -369,7 +369,8 @@
               <row class="- topic/row ">
                 <entry colname="col1" class="- topic/entry ">PostGIS Spatial and Geographic Objects
                   for Greenplum Database 6.0.x</entry>
-                <entry colname="col3" class="- topic/entry ">2.1.5+pivotal.2-2</entry>
+                <entry colname="col3" class="- topic/entry ">2.5.4+pivotal.1,
+                  2.1.5+pivotal.2-2</entry>
               </row>
             </tbody>
           </tgroup>