[build] Fix builds with -pedantic

Author: tmpsantos

include/mbgl/style/expression/is_constant.hpp

@@ -17,15 +17,15 @@ bool isGlobalPropertyConstant(const Expression& expression, const T& properties)
             }
         }
     }
-    
+
     bool isConstant = true;
     expression.eachChild([&](const Expression& e) {
         if (isConstant && !isGlobalPropertyConstant(e, properties)) {
             isConstant = false;
         }
     });
     return isConstant;
-};
+}
 
 bool isFeatureConstant(const Expression& expression);
 bool isZoomConstant(const Expression& e);