Fix compilation errors with gcc.

Change-Id: If88d4f639658db2d6d71f5abcad563211138fc4a
diff --git a/compiler/optimizing/code_generator_arm.cc b/compiler/optimizing/code_generator_arm.cc
index 696f5a8..04952be 100644
--- a/compiler/optimizing/code_generator_arm.cc
+++ b/compiler/optimizing/code_generator_arm.cc
@@ -707,6 +707,7 @@
     case Primitive::kPrimVoid:
       return Location();
   }
+
   UNREACHABLE();
 }