package/quazip: remove qt4 support

Qt4 support is about to be dropped, so remove the support from quazip as
well.

Also add an explicit depends on for qt5 for consistency with other packages.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>