telnet: Use C89 function definitions for two stragglers.

Reviewed by:	emaste
Differential Revision:	https://reviews.freebsd.org/D39528

contrib/telnet/telnet/commands.c

@@ -423,8 +423,7 @@ send_docmd(char *name)
 }
 
 static int
-send_dontcmd(name)
-    char *name;
+send_dontcmd(char *name)
 {
     return(send_tncmd(send_dont, "dont", name));
 }

contrib/telnet/telnet/ring.c

@@ -307,8 +307,7 @@ ring_encrypt(Ring *ring, void (*encryptor)(unsigned char *, int))
 }
 
 void
-ring_clearto(ring)
-    Ring *ring;
+ring_clearto(Ring *ring)
 {
     if (!ring_empty(ring))
 	ring->clearto = ring->supply;