Bump qt component version number

"qt" installer component moved from root repository into under
tools_generic. Force the installer to pick it from new location.

The root repository shall contain only single Updates.xml from now on.
It will contain only repository update includes, no package updates.

Change-Id: I7aa8c65e382f3f245ba4f5f0f1f453ffd0f15960
Reviewed-by: Jani Heikkinen <jani.heikkinen@theqtcompany.com>