nixos/release-notes: move "PHP config-file-scan-dir" from 16.09 to 17.03

Commits

351d12437 ("nixos/release-notes: PHP config-file-scan-dir /etc -> /etc/php.d")
41c8aa8d6 ("php: change config-file-scan-dir from /etc to /etc/php.d")

were merged to master _after_ NixOS 16.09. Commit 351d12437 then wrongly
updated the NixSO 16.09 release notes. Fix by moving the entry to NixOS
17.03.

nixos/doc/manual/release-notes/rl-1609.xml

···
       PHP has been upgraded to 7.0
     </para>
   </listitem>
-
-  <listitem>
-    <para>PHP now scans for extra configuration .ini files in /etc/php.d
-    instead of /etc. This prevents accidentally loading non-PHP .ini files
-    that may be in /etc.
-    </para>
-  </listitem>
-
 </itemizedlist>
 
 

nixos/doc/manual/release-notes/rl-1703.xml

···
       <literal>strippedName</literal>.
     </para>
   </listitem>
+
+  <listitem>
+    <para>PHP now scans for extra configuration .ini files in /etc/php.d
+    instead of /etc. This prevents accidentally loading non-PHP .ini files
+    that may be in /etc.
+    </para>
+  </listitem>
 </itemizedlist>