plat: fix switch statements to comply with MISRA rules

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

Change-Id: Ie4a7d2fd10f6141c0cfb89317ea28a755391622f
Signed-off-by: Jonathan Wright <jonathan.wright@arm.com>
diff --git a/plat/socionext/uniphier/uniphier_bl2_setup.c b/plat/socionext/uniphier/uniphier_bl2_setup.c
index 54b30e5..f7ae426 100644
--- a/plat/socionext/uniphier/uniphier_bl2_setup.c
+++ b/plat/socionext/uniphier/uniphier_bl2_setup.c
@@ -85,6 +85,7 @@
 		break;
 	default:
 		plat_error_handler(-ENOTSUP);
+		break;
 	}
 
 	if (!skip_scp) {