gnu: modular-qt: Add synopsis and descriptions for packages.
* gnu/packages/qt.scm (qtsvg, qtimageformats, qtx11extras,
qtxmlpatterns, qtdeclarative, qtdeclarative-render2d, qtconnectivity,
qtwebsockets, qtsensors, qtmultimedia, qtwayland, qtserialport,
qtserialbus, qtwebchannel, qtlocation, qttools, qtscript,
qtquickcontrols, qtquickcontrols2, qtgraphicaleffects, qtgamepad,
qtscxml, qtpurchasing, qtcanvas3d, qtdatavis3d, qtnetworkauth,
qtremoteobjects, qtspeech)[synopsis, description]: New fields.