vcl: unx: apply configuration to "Generic Printer" so it's PDF ...

... by default, instead of leaving it with
m_nPSLevel == 0 && m_nPDFDevice == 0.

Change-Id: I44059ac39791442602cbc48582670d98edc578ee
Reviewed-on: https://gerrit.libreoffice.org/66802
Tested-by: Jenkins
Reviewed-by: Michael Stahl <Michael.Stahl@cib.de>

vcl/unx/generic/printer/printerinfomanager.cxx

@@ -462,6 +462,9 @@ void PrinterInfoManager::initialize()
 
                 setDefaultPaper( aPrinter.m_aInfo.m_aContext );
 
+                // if it's a "Generic Printer", apply defaults from config...
+                aPrinter.m_aInfo.resolveDefaultBackend();
+
                 // finally insert printer
                 FileBase::getFileURLFromSystemPath( aFile.PathToFileName(), aPrinter.m_aFile );
                 aPrinter.m_aGroup       = aConfig.GetGroupName( nGroup );