data/dconf: Add Ctrl-semicolon to Emoji shortcut key

period key is needed Shift key in French keyboard and Ctrl-period does
not work.
Add Ctrl-semicolon in org.freedesktop.ibus.panel.emoji.hotkey to fix
the problem.

BUG=#2360

data/dconf/org.freedesktop.ibus.gschema.xml

@@ -183,7 +183,7 @@
       <description>The shortcut keys for turning Unicode typing on or off</description>
     </key>
     <key name="hotkey" type="as">
-      <default>[ '&lt;Control&gt;period' ]</default>
+      <default>[ '&lt;Control&gt;period', '&lt;Control&gt;semicolon' ]</default>
       <summary>Emoji shortcut keys for gtk_accelerator_parse</summary>
       <description>The shortcut keys for turning emoji typing on or off</description>
     </key>