pinctrl: sh-pfc: Validate enum IDs for regs with fixed-width fields

Add build-time checks to the PINMUX_CFG_REG() and PINMUX_DATA_REG()
macros, to ensure the number of provided enum IDs is correct.

This helps catching bugs early.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

drivers/pinctrl/sh-pfc/sh_pfc.h

@@ -130,7 +130,9 @@ struct pinmux_cfg_reg {
  */
 #define PINMUX_CFG_REG(name, r, r_width, f_width, ids)			\
 	.reg = r, .reg_width = r_width,					\
-	.field_width = f_width + BUILD_BUG_ON_ZERO(r_width % f_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 }
 
@@ -196,7 +198,9 @@ struct pinmux_data_reg {
  *          enum ID must be specified, all wrapped using the GROUP() macro.
  */
 #define PINMUX_DATA_REG(name, r, r_width, ids)				\
-	.reg = r, .reg_width = r_width,					\
+	.reg = r, .reg_width = r_width +				\
+	BUILD_BUG_ON_ZERO(sizeof((const u16 []) { ids }) / sizeof(u16) != \
+			  r_width),					\
 	.enum_ids = (const u16 [r_width]) { ids }
 
 struct pinmux_irq {