Fix openssl 1.1 installation

The `configure` command for OpenSSL 1.1 doesn't support `no-krb5`
option, and `no-ssl2` option was deprecated.

Fixes https://github.com/rbenv/ruby-build/pull/1053#issuecomment-276666932

bin/ruby-build

@@ -988,8 +988,11 @@ build_package_mac_openssl() {
   export KERNEL_BITS="64"
   OPENSSL_CONFIGURE="${OPENSSL_CONFIGURE:-./config}"
 
-  # Compile a shared lib with zlib dynamically linked, no kerberos.
-  package_option openssl configure --openssldir="$OPENSSLDIR" zlib-dynamic no-ssl2 no-ssl3 no-krb5 shared
+  local nokerberos
+  [[ "$1" != openssl-1.0.* ]] || nokerberos=1
+
+  # Compile a shared lib with zlib dynamically linked.
+  package_option openssl configure --openssldir="$OPENSSLDIR" zlib-dynamic no-ssl3 shared ${nokerberos:+no-ssl2 no-krb5}
 
   # Default MAKE_OPTS are -j 2 which can confuse the build. Thankfully, make
   # gives precedence to the last -j option, so we can override that.