simplify openssl setup in cmakelists
simplify openssl setup in cmakelists

Much of the openssl setup in the cmakelists is redundant or wrong. OPENSSL_INCLUDE_DIR is an output variable so we shouldn't be setting that. The openssl finding logic built in to cmake already looks at the OPENSSL_ROOT_DIR environment variable on its own so don't need to try to pass that. And on any unix it will already search for a pkgconfig file for openssl so don't really need to do anything on linux.

We do still need to keep something here for macOS as for whatever reason homebrew doesn't link in openssl's pkgconfig file (maybe due to concern of conflict?)

EOSIO/eos,EOSIO/eos,EOSIO/eos,EOSIO/eos,EOSIO/eos