always turn the fifo on

Reference: /n/atom/patch/applied/uartfifo
Date: Sun Jun  8 10:25:04 CES 2014
Signed-off-by: quanstro@quanstro.net

--- /sys/src/nix/port/devuart.c	Sun Jun  8 10:24:59 2014
+++ /sys/src/nix/port/devuart.c	Sun Jun  8 10:24:59 2014
@@ -81,6 +81,8 @@
 	p->cts = 1;
 	p->ctsbackoff = 0;
 
+//	if(p->fifo == 0)
+		uartctl(p, "i1");			/* controller expected to reject this if not available */
 	if(p->bits == 0)
 		uartctl(p, "l8");
 	if(p->stop == 0)