smollish improvement suggestions for memory (in openssl and for sensitive info)

[matu3ba]

I have used openssl recently (more in a hacky fashion).
You can take a look at this example:
https://github.com/matu3ba/dotfiles/blob/3831a171410f9bb2535648c9032e6e5ed8b5770f/example/openssl_aes.c#L192
It is very annoying that they renamed it from cleanup to free without adding a compile error on usage of the old function.

Note, that I dont use bzero to zero out memory, which should be done for sensitive information.
https://www.quaxio.com/wtf/openssl_wtf.html
I think @memset should do the same in Zig, but unfortunately the manual does not specify, if intrinsics could be optimized away by nasty LLVM.