title: Project ERROR: Unknown module(s) in QT: x11extras
body: <p>I'm trying to build the pyqtdeploy-sysroot containing Qt5 and PyQt5 for the current machine (x86_64 system).
  I tried Qt5 versions 5.15.0, 5.15.1 or 5.15.2 on a Fedora 30 (tried 31 and 32 as well as Debian 10 and Ubuntu 18.04, too) system using pyqtdeploy 3.0, 3.1 and 3.1.1.
  On all systems I've installed all build dependencies I can think of:</p>
  <pre><code>python python3 python3-pip libssl-dev zlib1g-dev pyqt5-dev libqt5x11extras5-dev libgles2-mesa-dev
  </code></pre>
  <p>I event tried installing <code>*x11*-dev</code> and <code>*gl*-dev</code> (<code>-devel</code> respectively) :)</p>
  <p>I always run into the following problem:</p>
  <pre><code>Running 'sip-install --qmake /home/frans/_HOME/2011_pyqt/docker_home/demo/sysroot-linux-64/Qt/bin/qmake --no-distinfo --concatenate 2 --no-docstrings --verbose'.
  Querying qmake about your Qt installation...
  /home/frans/_HOME/2011_pyqt/docker_home/demo/sysroot-linux-64/Qt/bin/qmake -query
  This is the GPL version of PyQt 5.15.0 (licensed under the GNU General Public License) for Python 3.7.7 on linux.
  Found the license file 'pyqt-gpl.sip'.
  These bindings will be built: QtCore, QtNetwork, QtGui, QtWidgets, QtX11Extras.
  Generating the QtCore bindings...
  Generating the QtNetwork bindings...
  Generating the QtGui bindings...
  Generating the QtWidgets bindings...
  Generating the QtX11Extras bindings...
  Generating the .pro file for the QtCore module...
  Generating the .pro file for the QtNetwork module...
  Generating the .pro file for the QtGui module...
  Generating the .pro file for the QtWidgets module...
  Generating the .pro file for the QtX11Extras module...
  Generating the top-level .pro file...
  Generating the Makefiles...
  /home/frans/_HOME/2011_pyqt/docker_home/demo/sysroot-linux-64/Qt/bin/qmake -recursive PyQt5.pro
  sip-install: '/home/frans/_HOME/2011_pyqt/docker_home/demo/sysroot-linux-64/Qt/bin/qmake -recursive PyQt5.pro' failed returning 3
  Info: creating stash file /tmp/tmp1_ng3eyh/.qmake.stash
  Reading /tmp/tmp1_ng3eyh/QtCore/QtCore.pro
  Reading /tmp/tmp1_ng3eyh/QtNetwork/QtNetwork.pro
  Reading /tmp/tmp1_ng3eyh/QtGui/QtGui.pro
  Reading /tmp/tmp1_ng3eyh/QtWidgets/QtWidgets.pro
  Reading /tmp/tmp1_ng3eyh/QtX11Extras/QtX11Extras.pro
  Project ERROR: Unknown module(s) in QT: x11extras
  pyqtdeploy-sysroot: execution of 'sip-install' failed: returned exit code 1
  </code></pre>
  <p>I'm trying basically the same thing as this guy: <a href="https://www.riverbankcomputing.com/pipermail/pyqt/2020-September/043203.html" rel="nofollow noreferrer">https://www.riverbankcomputing.com/pipermail/pyqt/2020-September/043203.html</a> - but it seems like he had given up and switched to iOS..</p>
  <p>Any idea what I can do to investigate this behavior? I didn't modify anything regarding pyqtdeploy, Qt5, or the demo, all I'm doing is</p>
  <pre><code>pip3 install pyqtdeploy sip PyQt-builder
  wget https://files.pythonhosted.org/packages/ab/8c/1416eaed51c87a5ac934ee982e5c6e0a9dcab8d9b0b0461d4b8b259db5f6/pyqtdeploy-3.1.0.tar.gz
  tar xf pyqtdeploy-3.1.0.tar.gz
  cd pyqtdeploy-3.1.0/demo
  python3 build-demo.py --verbose
  </code></pre>