pcmcia: db1xxx_ss: Mark expected switch fall-throughs

Mark switch cases where we are expecting to fall through.

This patch fixes the following warnings (Building: db1xxx_defconfig mips):

drivers/pcmcia/db1xxx_ss.c:257:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/pcmcia/db1xxx_ss.c:269:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

drivers/pcmcia/db1xxx_ss.c

@@ -255,8 +255,10 @@ static int db1x_pcmcia_configure(struct pcmcia_socket *skt,
 	switch (state->Vcc) {
 	case 50:
 		++v;
+		/* fall through */
 	case 33:
 		++v;
+		/* fall through */
 	case 0:
 		break;
 	default:
@@ -267,9 +269,11 @@ static int db1x_pcmcia_configure(struct pcmcia_socket *skt,
 	switch (state->Vpp) {
 	case 12:
 		++p;
+		/* fall through */
 	case 33:
 	case 50:
 		++p;
+		/* fall through */
 	case 0:
 		break;
 	default: