This reuses the ResourceFileMapper and extends it slightly to return
full paths on request. Subsequently, this is moved into a shared
directory inside tools.
Fixes: QTBUG-55259
Change-Id: Ice5fc68d03b767a4185742e182556ab4290bd28d
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>