remove unsupported tag MaintenanceTitle

Newer versions of the installer framework continue only
with supported tags inside the installer config.xml file.

Change-Id: I87c0e8f079023b5ba7cf7cca248e1fa310b7a97e
Reviewed-by: Niels Weber <niels.weber@digia.com>
Reviewed-by: Eike Ziller <eike.ziller@digia.com>

dist/installer/ifw/config/config-linux.xml.in

@@ -3,7 +3,6 @@
     <Name>Qt Creator</Name>
     <Version>{version}</Version>
     <Title>Qt Creator {version}</Title>
-    <MaintenanceTitle>Qt Creator Maintenance</MaintenanceTitle>
     <Publisher>Qt Project</Publisher>
     <ProductUrl>http://qt-project.org</ProductUrl>
 

dist/installer/ifw/config/config-windows.xml.in

@@ -3,7 +3,6 @@
     <Name>Qt Creator</Name>
     <Version>{version}</Version>
     <Title>Qt Creator {version}</Title>
-    <MaintenanceTitle>Qt Creator Maintenance</MaintenanceTitle>
     <Publisher>Qt Project</Publisher>
     <ProductUrl>http://qt-project.org</ProductUrl>