[sets] drop zydas firmare packages from @wireless set
Revert "[sets] drop zydas firmare packages from @wireless set"

This reverts commit 4aaa4b8b58574cb10760f49919a889beb7419e08.
[sets] firmware packages have been moved to sys-firmware/
[sets] wireless: prism54-firmware is still in net-wireless/
[sets] wireless: prism54-firmware:0 has been dropped
[sets] wireless: rtl8192su-firmware is still in net-wireless/