Fixed warnings on Win64

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

src/dist.cpp

@@ -139,7 +139,7 @@ void zmq::dist_t::distribute (msg_t *msg_, int flags_)
 
     //  Add matching-1 references to the message. We already hold one reference,
     //  that's why -1.
-    msg_->add_refs (matching - 1);
+    msg_->add_refs ((int) matching - 1);
 
     //  Push copy of the message to each matching pipe.
     for (pipes_t::size_type i = 0; i < matching;) {

src/socket_base.cpp

@@ -776,7 +776,7 @@ void zmq::socket_base_t::process_term (int linger_)
     //  Ask all attached pipes to terminate.
     for (pipes_t::size_type i = 0; i != pipes.size (); ++i)
         pipes [i]->terminate (false);
-    register_term_acks (pipes.size ());
+    register_term_acks ((int) pipes.size ());
 
     //  Continue the termination process immediately.
     own_t::process_term (linger_);