make con(1) ask the eia driver to use fifos whenever it sets a baud rate
i.e. when it is talking to a real eia device and not a /srv fd or the like.
(jmk knows).

-Steve

Reference: /n/sources/patch/applied/con-fifos
Date: Tue Feb 19 16:45:08 CET 2008
Signed-off-by: steve@quintile.net

--- /sys/src/cmd/con/con.c	Tue Feb 19 16:43:21 2008
+++ /sys/src/cmd/con/con.c	Tue Feb 19 16:43:17 2008
@@ -232,8 +232,10 @@
 	snprint(cname, sizeof cname, "%sctl", dest);
 	ctl = open(cname, ORDWR);
 	if (baud > 0) {
-		if(ctl >= 0)
+		if(ctl >= 0){
 			fprint(ctl, "b%d", baud);
+			fprint(ctl, "i1");		// use fifos if available
+		}
 		else
 			fprint(2, "con: cannot open %s: %r\n", cname);
 	}