Fix exhaustive switches

Summary:
X-link: https://github.com/facebook/react-native/pull/52379

Changelog: [General][Fixed] - Add `default:` case to avoid warnings/errors for targets that compile with `-Wswitch-enum` and `-Wswitch-default` enabled

Reviewed By: aary, yungsters, astreet

Differential Revision: D77051152

fbshipit-source-id: 100b10f97cb3a5d73f1e3dcaf1b284baf6a43982

yoga/YGValue.h

@@ -72,9 +72,9 @@ inline bool operator==(const YGValue& lhs, const YGValue& rhs) {
     case YGUnitPoint:
     case YGUnitPercent:
       return lhs.value == rhs.value;
+    default:
+      return false;
   }
-
-  return false;
 }
 
 inline bool operator!=(const YGValue& lhs, const YGValue& rhs) {