pinctrl: lpc18xx: mark expected switch fall-throughs

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Addresses-Coverity-ID: 1292308 ("Missing break in switch")
Addresses-Coverity-ID: 1292309 ("Missing break in switch")
Addresses-Coverity-ID: 1309546 ("Missing break in switch")
Addresses-Coverity-ID: 1357369 ("Missing break in switch")
Addresses-Coverity-ID: 1357389 ("Missing break in switch")
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/pinctrl-lpc18xx.c

@@ -844,8 +844,11 @@ static int lpc18xx_pconf_get_pin(struct pinctrl_dev *pctldev, unsigned param,
 		*arg = (reg & LPC18XX_SCU_PIN_EHD_MASK) >> LPC18XX_SCU_PIN_EHD_POS;
 		switch (*arg) {
 		case 3: *arg += 5;
+			/* fall through */
 		case 2: *arg += 5;
+			/* fall through */
 		case 1: *arg += 3;
+			/* fall through */
 		case 0: *arg += 4;
 		}
 		break;
@@ -1060,8 +1063,11 @@ static int lpc18xx_pconf_set_pin(struct pinctrl_dev *pctldev, unsigned param,
 
 		switch (param_val) {
 		case 20: param_val -= 5;
+			 /* fall through */
 		case 14: param_val -= 5;
+			 /* fall through */
 		case  8: param_val -= 3;
+			 /* fall through */
 		case  4: param_val -= 4;
 			 break;
 		default: