Remove ecma_simple_value_t and refactor ecma_make_simple_value (#2135)

This patch removes all ecma_make_simple_value calls to make the code more easy to understand.
Also removes the type ecma_simple_value_t which improves the performance in related code paths by calculating the value of new ecma_value_t is no longer needed.

JerryScript-DCO-1.0-Signed-off-by: Robert Fancsik frobert@inf.u-szeged.hu

jerry-core/ecma/operations/ecma-reference.c

@@ -105,7 +105,7 @@ ecma_op_resolve_reference_value (ecma_object_t *lex_env_p, /**< starting lexical
 
         if (getter_p == NULL)
         {
-          return ecma_make_simple_value (ECMA_SIMPLE_VALUE_UNDEFINED);
+          return ECMA_VALUE_UNDEFINED;
         }
 
         ecma_value_t base_value = ecma_make_object_value (binding_obj_p);