Remove PythonQt support -- C++ bits

src/libcalamares/modulesystem/Descriptor.cpp

@@ -40,7 +40,6 @@ interfaceNames()
         { QStringLiteral("process"), Interface::Process },
         { QStringLiteral("qtplugin"), Interface::QtPlugin },
         { QStringLiteral("python"), Interface::Python },
-        { QStringLiteral("pythonqt"), Interface::PythonQt }
     };
     // *INDENT-ON*
     // clang-format on
@@ -98,7 +97,6 @@ Descriptor::fromDescriptorData( const QVariantMap& moduleDesc )
         consumedKeys << "load";
         break;
     case Interface::Python:
-    case Interface::PythonQt:
         d.m_script = CalamaresUtils::getString( moduleDesc, "script" );
         if ( d.m_script.isEmpty() )
         {

src/libcalamares/modulesystem/Descriptor.h

@@ -42,7 +42,6 @@ enum class Interface
     QtPlugin,  // Jobs or Views
     Python,  // Jobs only
     Process,  // Deprecated interface
-    PythonQt  // Views only, available as enum even if PythonQt isn't used
 };
 const NamedEnumTable< Interface >& interfaceNames();
 
@@ -111,7 +110,7 @@ public:
      */
     QString script() const
     {
-        return ( m_interface == Interface::Python || m_interface == Interface::PythonQt ) ? m_script : QString();
+        return m_interface == Interface::Python ? m_script : QString();
     }
 
 private:

src/libcalamaresui/modulesystem/ModuleFactory.cpp

@@ -55,10 +55,6 @@ moduleFromDescriptor( const Calamares::ModuleSystem::Descriptor& moduleDescripto
         {
             m.reset( new ViewModule() );
         }
-        else if ( moduleDescriptor.interface() == Interface::PythonQt )
-        {
-            cError() << "PythonQt view modules are not supported in this version of Calamares.";
-        }
         else
         {
             cError() << "Bad interface"