cold-flash: Increase timeout after leaving cold flash mode

Switching to NOLO takes about one second and NOLO itself wait another second. So it should be OK.

src/cold-flash.c

@@ -415,7 +415,7 @@ int leave_cold_flash(struct usb_device_info * dev) {
 	if ( ret != sizeof(omap_memory_msg) )
 		ERROR_RETURN("Sending OMAP memory boot message failed", -1);
 
-	SLEEP(250000);
+	SLEEP(1000000);
 	return 0;
 
 }