pinctrl: sh-pfc: r8a7792: Fix vin1_data18_b pin group

The vin1_data18_b pin group itself is present, but it is not listed in
the VIN1 pin group array, and thus cannot be selected.

Fixes: 7dd74bb1 ("pinctrl: sh-pfc: r8a7792: Add VIN pin groups")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>

drivers/pinctrl/sh-pfc/pfc-r8a7792.c

@@ -1913,6 +1913,7 @@ static const char * const vin1_groups[] = {
 	"vin1_data8",
 	"vin1_data24_b",
 	"vin1_data20_b",
+	"vin1_data18_b",
 	"vin1_data16_b",
 	"vin1_sync",
 	"vin1_field",