serial: sh-sci: Simplify multiplication/shift logic

"a * (1 << b)" == "a << b".

No change in generated code.
Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/118d62e167f6cf5e98bdf9a738634b4590ea8d09.1645460901.git.geert+renesas@glider.beSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/sh-sci.c

@@ -2293,7 +2293,7 @@ static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
 	for_each_sr(sr, s) {
 		for (c = 0; c <= 3; c++) {
 			/* integerized formulas from HSCIF documentation */
-			prediv = sr * (1 << (2 * c + 1));
+			prediv = sr << (2 * c + 1);
 
 			/*
 			 * We need to calculate: