remove gcc 3.3 and snx ("SSL Network Extender")

SNX is the only package that I could find to depend on GCC 3.3, and it appears to be rather obscure.

SNX seems to be pretty obscure and was added and later disowned by @peti. It does not build in the current form but does when adjusting the hash.

I plan to merge (remove) this if there is no request to the contrary within 7 days.