Use string instead of string_view for embedded ck headers; use safe default instance for ck_gemm

src/targets/gpu/include/migraphx/gpu/ck.hpp

@@ -59,14 +59,14 @@ std::string ck_disable_warnings(P p)
                               {{"content", std::string{p.data(), p.size()}}});
 }
 
-static std::unordered_map<std::string_view, std::string_view> create_ck_header_strings()
+static std::unordered_map<std::string, std::string> create_ck_header_strings()
 {
-    std::unordered_map<std::string_view, std::string_view> result;
+    std::unordered_map<std::string, std::string> result;
     auto ck_headers = ck::host::GetHeaders();
 
     std::transform(
         ck_headers.begin(), ck_headers.end(), std::inserter(result, result.begin()), [&](auto& p) {
-            return std::pair<std::string_view, std::string_view>(p.first,
+            return std::pair<std::string, std::string>(p.first,
                                                                  ck_disable_warnings(p.second));
         });
     return result;

src/targets/gpu/jit/ck_gemm.cpp

@@ -135,7 +135,7 @@ struct ck_gemm_compiler : compiler<ck_gemm_compiler>
     operation compile_op(context& ctx, const std::vector<shape>& inputs, const value& v) const
     {
         const auto& c_shape = inputs.back();
-        auto tuning_value   = v.get("tuning_value", 0);
+        auto tuning_value   = v.get("tuning_value", 34);
         auto batch_count = get_batch_count(c_shape);
         auto problem     = create_problem(inputs, v);