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/arm/cci/cci.c b/drivers/arm/cci/cci.c
index e156838..81808b9 100644
--- a/drivers/arm/cci/cci.c
+++ b/drivers/arm/cci/cci.c
@@ -83,22 +83,25 @@
  */
 static int get_slave_ports(unsigned int part_num)
 {
-	/* Macro to match CCI products */
-#define RET_ON_MATCH(product) \
-	case CCI ## product ## _PART_NUM: \
-		return CCI ## product ## _SLAVE_PORTS
+	int num_slave_ports = -1;
 
 	switch (part_num) {
 
-	RET_ON_MATCH(400);
-	RET_ON_MATCH(500);
-	RET_ON_MATCH(550);
-
+	case CCI400_PART_NUM:
+		num_slave_ports = CCI400_SLAVE_PORTS;
+		break;
+	case CCI500_PART_NUM:
+		num_slave_ports = CCI500_SLAVE_PORTS;
+		break;
+	case CCI550_PART_NUM:
+		num_slave_ports = CCI550_SLAVE_PORTS;
+		break;
 	default:
-		return -1;
+		/* Do nothing in default case */
+		break;
 	}
 
-#undef RET_ON_MATCH
+	return num_slave_ports;
 }
 #endif /* ENABLE_ASSERTIONS */
 
diff --git a/drivers/arm/gic/v2/gicv2_main.c b/drivers/arm/gic/v2/gicv2_main.c
index 7e2c7a7..e25e501 100644
--- a/drivers/arm/gic/v2/gicv2_main.c
+++ b/drivers/arm/gic/v2/gicv2_main.c
@@ -459,6 +459,7 @@
 		break;
 	default:
 		assert(0);
+		break;
 	}
 	spin_unlock(&gic_lock);
 }
diff --git a/drivers/arm/gic/v3/gicv3_main.c b/drivers/arm/gic/v3/gicv3_main.c
index f4a3ef8..d8fc7d6 100644
--- a/drivers/arm/gic/v3/gicv3_main.c
+++ b/drivers/arm/gic/v3/gicv3_main.c
@@ -1004,6 +1004,7 @@
 		break;
 	default:
 		assert(0);
+		break;
 	}
 
 	if (id < MIN_SPI_ID) {