drivers: fix switch statements to comply with MISRA rules

Ensure (where possible) that switch statements in drivers comply with
MISRA rules 16.1 - 16.7.

Change-Id: I7a91e04b02af80fbc4673a52293386c0f81a0f7a
Signed-off-by: Jonathan Wright <jonathan.wright@arm.com>
diff --git a/drivers/ufs/ufs.c b/drivers/ufs/ufs.c
index 254866f..515fc27 100644
--- a/drivers/ufs/ufs.c
+++ b/drivers/ufs/ufs.c
@@ -271,6 +271,7 @@
 		break;
 	default:
 		assert(0);
+		break;
 	}
 	if (hd->dd == DD_IN)
 		flush_dcache_range(buf, length);
@@ -359,6 +360,7 @@
 		break;
 	default:
 		assert(0);
+		break;
 	}
 	flush_dcache_range((uintptr_t)utrd, sizeof(utp_utrd_t));
 	flush_dcache_range((uintptr_t)utrd->header, UFS_DESC_SIZE);
@@ -511,6 +513,9 @@
 	case QUERY_WRITE_ATTR:
 		assert(((buf & 3) == 0) && (size != 0));
 		break;
+	default:
+		/* Do nothing in default case */
+		break;
 	}
 	get_utrd(&utrd);
 	ufs_prepare_query(&utrd, op, idn, index, sel, buf, size);
@@ -533,6 +538,9 @@
 		       (void *)(utrd.resp_upiu + sizeof(query_resp_upiu_t)),
 		       size);
 		break;
+	default:
+		/* Do nothing in default case */
+		break;
 	}
 	(void)result;
 }