Position the break statement in the proper place

That is, AFTER the statement of the case label. Alternatively speaking,
resolve dead code problem.

Change-Id: Ia3e896da908f42939148fffd14c480ca73c1be4b
Reviewed-by: Tomi Korpipää <tomi.korpipaa@qt.io>

src/datavisualizationqml2/declarativetheme.cpp

@@ -201,8 +201,8 @@ void DeclarativeTheme3D::setThemeGradient(ColorGradient *gradient, GradientType
         Q3DTheme::setSingleHighlightGradient(newGradient);
         break;
     case GradientTypeMultiHL:
-        break;
         Q3DTheme::setMultiHighlightGradient(newGradient);
+        break;
     default:
         qWarning("Incorrect usage. Type may be GradientTypeSingleHL or GradientTypeMultiHL.");
         break;