trivial: add another screenshot of the firmware dialog

docs/html/img/Makefile.am

@@ -36,6 +36,7 @@ IMAGE_FILES =					\
 	gpk-waiting.png				\
 	gpk-remove-confirm.png			\
 	gpk-distro-upgrade-notify.png		\
+	gpk-client-firmware.png			\
 	gpk-client-codecs.png			\
 	gpk-client-mime-type.png		\
 	gpk-client-font.png			\

docs/html/pk-screenshots.html

@@ -156,6 +156,14 @@
   <p class="caption"><a href="http://en.wikipedia.org/wiki/Markdown">Markdown</a> syntax in the update viewer</p>
 </td>
 </tr>
+<tr>
+<td width="300">
+  <center><a href="img/gpk-client-firmware.png"><img src="img/thumbnails/gpk-client-firmware.png" alt=""/></a></center>
+  <p class="caption">Search for required firmware in packages</p>
+</td>
+<td width="300">&nbsp</td>
+<td width="300">&nbsp</td>
+</tr>
 </table>
 </center>