ALSA: galaxy: Mark expected switch fall-throughs

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

Addresses-Coverity-ID: 1468367 ("Missing break in switch")
Addresses-Coverity-ID: 115037 ("Missing break in switch")
Addresses-Coverity-ID: 115038 ("Missing break in switch")
Signed-off-by: Gustavo A. R. Silva <[e-mail]>
Signed-off-by: Takashi Iwai <[e-mail]>

sound/isa/galaxy/galaxy.c

···
 		break;
 	case 2:
 		irq[n] = 9;
+		/* Fall through */
 	case 9:
 		wss_config[n] |= WSS_CONFIG_IRQ_9;
 		break;
···
 	case 1:
 		if (dma1[n] == 0)
 			break;
+		/* Fall through */
 	default:
 		dev_err(dev, "invalid capture DMA %d\n", dma2[n]);
 		return 0;
···
 		break;
 	case 2:
 		mpu_irq[n] = 9;
+		/* Fall through */
 	case 9:
 		config[n] |= GALAXY_CONFIG_MPUIRQ_2;
 		break;