socket.rb: protected connect_internal

* ext/socket/lib/socket.rb (Addrinfo#connect_internal): make
  protected for Addrinfo#connect_to, instead of private and send.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@62449 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ext/socket/lib/socket.rb

@@ -77,7 +77,7 @@ class Addrinfo
       sock
     end
   end
-  private :connect_internal
+  protected :connect_internal
 
   # :call-seq:
   #   addrinfo.connect_from([local_addr_args], [opts]) {|socket| ... }
@@ -158,7 +158,7 @@ class Addrinfo
   #
   def connect_to(*args, timeout: nil, &block)
     remote_addrinfo = family_addrinfo(*args)
-    remote_addrinfo.send(:connect_internal, self, timeout, &block)
+    remote_addrinfo.connect_internal(self, timeout, &block)
   end
 
   # creates a socket bound to self.