Fixed syntax issue between GCC and Clang/Visual Studio

Author: jwellbelove

include/etl/parameter_pack.h

@@ -134,17 +134,17 @@ namespace etl
   inline constexpr size_t parameter_pack_v = etl::parameter_pack<TTypes...>::template index_of_type<T>::value;
 #endif
 
-#if ETL_USING_CPP17 && (!ETL_USING_GCC_COMPILER || (__GNUC__ > 7))
-  //***********************************
-  template <typename... TTypes>
-  template <typename T>
-  constexpr size_t parameter_pack<TTypes...>::template index_of_type<T>::value;
-#else
+//#if ETL_USING_CPP17 && !ETL_USING_GCC_COMPILER
+//  //***********************************
+//  template <typename... TTypes>
+//  template <typename T>
+//  constexpr size_t parameter_pack<TTypes...>::template index_of_type<T>::value;
+//#else
   //***********************************
   template <typename... TTypes>
   template <typename T>
   constexpr size_t parameter_pack<TTypes...>::index_of_type<T>::value;
-#endif
+//#endif
 }
 #endif
 #endif

test/test_parameter_pack.cpp

@@ -34,7 +34,7 @@ namespace
 {
   using Pack = etl::parameter_pack<char, short, int>;
 
-  SUITE(test_type_lookup)
+  SUITE(test_parameter_pack)
   {
     //*************************************************************************
     TEST(test_index_of_type)