De-memsetify Wii_SSL and fix segfault.

Fixes #7917
The first memset was clearing the delicate bits of the std::string
in the struct, causing segfaults.

I also removed the rest of the memsets because they were paranoid,
unneeded and waseful. We shouldn't be managing the ssl libraries
structs for it.
I checked and the ssl library's functions were already memsetting
those structs as needed.
Merge pull request #1704 from phire/wii_ssl_segfault

De-memsetify Wii_SSL and fix segfault.