Move updating of the window size to the monitor process.

This will allow us to close the slave in the main sudo process in
the future so only the command and monitor have it open.

src/sudo.h

@@ -172,11 +172,12 @@ struct command_details {
 
 /* Status passed between parent and child via socketpair */
 struct command_status {
-#define CMD_INVALID 0
-#define CMD_ERRNO 1
-#define CMD_WSTATUS 2
-#define CMD_SIGNO 3
-#define CMD_PID 4
+#define CMD_INVALID	0
+#define CMD_ERRNO	1
+#define CMD_WSTATUS	2
+#define CMD_SIGNO	3
+#define CMD_PID		4
+#define CMD_TTYWINCH	5
     int type;
     int val;
 };