Patch to fix build with Qt 5.5, taken from upstream:
   https://github.com/lxde/liblxqt/commit/7303ea207de0771d6f450a31ec4a1ce69202869b

diff -u -r liblxqt-0.9.0.orig/lxqtnotification.h liblxqt-0.9.0/lxqtnotification.h
--- liblxqt-0.9.0.orig/lxqtnotification.h	2015-07-27 22:49:05.365166482 +0200
+++ liblxqt-0.9.0/lxqtnotification.h	2015-07-27 22:49:36.897606619 +0200
@@ -25,6 +25,7 @@
 #ifndef LXQTNOTIFICATION_H
 #define LXQTNOTIFICATION_H
 
+#include <QObject>
 #include <QStringList>
 #include "lxqtglobals.h"
 
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<tr><td><span title='2020-09-21 00:31:15 +0200'>2020-09-21</span></td><td><a href='/guix/commit/gnu/installer/newt/locale.scm?id=e1f3788944ee154ba9b33c891c4ccf039a1ff39a'>installer: Fix docstring typoes.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>