Remove a few unneeded "QT += xml"s

Must at some point in time have been changed to use QXmlStream*

Change-Id: I8ed535f51246a0917454352d459a0f24c34f4a62
Reviewed-by: Alessandro Portale <alessandro.portale@theqtcompany.com>

src/libs/qmljs/qmljs.pro

 DEFINES += QMLJS_BUILD_DIR
 
-QT +=script xml
+QT +=script
+
 include(../../qtcreatorlibrary.pri)
 include(qmljs-lib.pri)

src/plugins/beautifier/beautifier.pro

 include(../../qtcreatorplugin.pri)
 
-QT += xml
-
 HEADERS += \
     abstractsettings.h \
     beautifierabstracttool.h \

src/plugins/designer/designer.pro

@@ -4,7 +4,7 @@ include(../../qtcreatorplugin.pri)
 include(../../shared/designerintegrationv2/designerintegration.pri)
 include(cpp/cpp.pri)
 
-QT += printsupport designer designercomponents-private xml
+QT += printsupport designer designercomponents-private
 
 HEADERS += formeditorplugin.h \
         formeditorfactory.h \

src/plugins/projectexplorer/projectexplorer.pro

-QT += quick script xml
+QT += quick script
 
 include(../../qtcreatorplugin.pri)
 include(customwizard/customwizard.pri)

src/tools/valgrindfake/valgrindfake.pro

 TEMPLATE = app
 TARGET = valgrind-fake
 
-QT += network xml
+QT += network
 QT -= gui widgets
 
 macx:CONFIG -= app_bundle