pinctrl: renesas: Simplify multiplication/shift logic

"a * (1 << b)" == "a << b".
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/31eaa3226c61ecf653e2b031307eea42a9a3d54e.1645460548.git.geert+renesas@glider.be

drivers/pinctrl/renesas/sh_pfc.h

@@ -132,9 +132,8 @@ struct pinmux_cfg_reg {
 	.reg = r, .reg_width = r_width,					\
 	.field_width = f_width + BUILD_BUG_ON_ZERO(r_width % f_width) +	\
 	BUILD_BUG_ON_ZERO(sizeof((const u16 []) { ids }) / sizeof(u16) != \
-			  (r_width / f_width) * (1 << f_width)),	\
-	.enum_ids = (const u16 [(r_width / f_width) * (1 << f_width)])	\
-		{ ids }
+			  (r_width / f_width) << f_width),		\
+	.enum_ids = (const u16 [(r_width / f_width) << f_width]) { ids }
 
 /*
  * Describe a config register consisting of several fields of different widths