Remove unnecessary duplicate statement

This was incorrectly added in a recent CL.

Test: atest aidl_unittests aidl_integration_test
Change-Id: I94f6bbe8a77709f68b12e4225f9e8771c423f2d7
diff --git a/aidl_to_cpp.cpp b/aidl_to_cpp.cpp
index 33bbb2b..b7d48b4 100644
--- a/aidl_to_cpp.cpp
+++ b/aidl_to_cpp.cpp
@@ -293,11 +293,6 @@
       AddHeaders(*parameter, typenames, headers);
     }
   }
-  if (type.IsGeneric()) {
-    for (const auto& parameter : type.GetTypeParameters()) {
-      AddHeaders(*parameter, typenames, headers);
-    }
-  }
   if (isNullable) {
     if (type.GetName() != "IBinder") {
       headers->insert("optional");