No package generated against Symbian^3 SDK should have Symbian^1 platforms as dependencies

After some debate related to QTBUG-17150, it turned out that it is not just Qt.sis that is not backwards compatible between Symbian^3 and Symbian^1; this problem is universal for all Qt applications. It seems to stem from the fact that Symbian^3 builds link to a newer implementation of stdcpp library. In any case, the fix done for QTBUG-17150 needs to be made to apply to all Qt projects.