Added vulkan_from_string.hpp.

include/vulkan/vulkan_from_string.hpp

@@ -14,6 +14,7 @@
 
 namespace VULKAN_HPP_NAMESPACE
 {
+
 #define VULKAN_HPP_ENUM_FROM_STRING_STORAGE                                                   \
   namespace VULKAN_HPP_NAMESPACE                                                              \
   {                                                                                           \
@@ -4401,10 +4402,7 @@ namespace VULKAN_HPP_NAMESPACE
   VULKAN_HPP_STORAGE_API extern const EnumFromStringMap enumFromStringMap;
 
   template <typename TEnum>
-  std::optional<TEnum> from_string( const std::string & )
-  {
-      static_assert(false, "Not a Vulkan enum type.");
-  }
+  std::optional<TEnum> from_string( const std::string & );
 
   //=== VK_VERSION_1_0 ===