Properly link flecs library

engine/libs/flecs/examples/cpp/queries/wildcards/src/main.cpp

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+#include <wildcards.h>
+#include <iostream>
+
+// Queries can have wildcard terms that can match multiple instances of a
+// relationship or relationship target.
+
+struct Eats {
+    int amount;
+};
+
+struct Apples { };
+struct Pears { };
+
+int main(int, char *[]) {
+    flecs::world ecs;
+
+    // Create a query that matches edible components
+    flecs::query<Eats> q = ecs.query_builder<Eats>()
+        .term_at(1).second(flecs::Wildcard) // Change first argument to (Eats, *)
+        .build();
+
+    // Create a few entities that match the query
+    ecs.entity("Bob")
+        .set<Eats, Apples>({10})
+        .set<Eats, Pears>({5});
+
+    ecs.entity("Alice")
+        .set<Eats, Apples>({4});
+
+    // Iterate the query with a flecs::iter. This makes it possible to inspect
+    // the pair that we are currently matched with.
+    q.each([](flecs::iter& it, size_t index, Eats& eats) {
+        flecs::entity e = it.entity(index);
+        flecs::entity food = it.pair(1).second();
+
+        std::cout << e.name() << " eats " 
+            << eats.amount << " " << food.name() << std::endl;
+    });
+
+    // Output:
+    //   Bob eats 10 Apples
+    //   Bob eats 5 Pears
+    //   Alice eats 4 Apples    
+}