serial: sh-sci: Drop useless check for zero sampling_rate

sci_port.sampling_rate is always non-zero, except for HSCIF, which uses
sci_baud_calc_hscif() instead of sci_scbrr_calc().
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/sh-sci.c

@@ -1863,13 +1863,7 @@ static void sci_shutdown(struct uart_port *port)
 static unsigned int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
 				   unsigned long freq)
 {
-	if (s->sampling_rate)
-		return DIV_ROUND_CLOSEST(freq, s->sampling_rate * bps) - 1;
-
-	/* Warn, but use a safe default */
-	WARN_ON(1);
-
-	return ((freq + 16 * bps) / (32 * bps) - 1);
+	return DIV_ROUND_CLOSEST(freq, s->sampling_rate * bps) - 1;
 }
 
 /* calculate frame length from SMR */