uftp3 @3.7.2: does not build with openssl 1.1

[ryandesign (Ryan Carsten Schmidt)]

​https://build.macports.org/builders/ports-10.15_x86_64-builder/builds/15975/steps/install-port/logs/stdio

encrypt_openssl.c:184:20: error: variable has incomplete type 'EVP_CIPHER_CTX' (aka 'struct evp_cipher_ctx_st')
    EVP_CIPHER_CTX ctx;
                   ^

etc.

Also, we might update to 3.7.3, and/or make a uftp4 port.