Quash a load of compile warnings

Kevin Lyda writes:
I enclose the following patch which removes all but three of the warnings.  i
don't have any non-linux systems handy to test a fix to the round() function.
but having it return a double should be fine.

It doesn't actually fix anything, it just shuts up -Wall, so it's certainly an
optional type of patch.

cmdmon.c

@@ -1584,7 +1584,7 @@ read_from_cmd_socket(void *anything)
   CMD_Reply tx_message, *prev_tx_message;
   int rx_message_length, tx_message_length;
   struct sockaddr_in where_from;
-  int from_length;
+  socklen_t from_length;
   unsigned long remote_ip;
   unsigned short remote_port;
   int md5_ok;