allow control endpoint's timeout to be changed

Reference: /n/atom/patch/applied/usbctltmout
Date: Sat May  3 02:32:26 CES 2014
Signed-off-by: quanstro@quanstro.net

--- /sys/src/nix/port/devusb.c	Sat May  3 02:32:19 2014
+++ /sys/src/nix/port/devusb.c	Sat May  3 02:32:21 2014
@@ -1300,8 +1300,8 @@
 		break;
 	case CMtmout:
 		deprint("usb epctl %s\n", cb->f[0]);
-		if(ep->ttype == Tiso || ep->ttype == Tctl)
-			error("ctl ignored for this endpoint type");
+		if(ep->ttype == Tiso /*|| ep->ttype == Tctl*/)
+			error("timeout ignored for this endpoint type");
 		ep->tmout = strtoul(cb->f[1], nil, 0);
 		if(ep->tmout != 0 && ep->tmout < Xfertmout)
 			ep->tmout = Xfertmout;