Removed unneeded Vulkan symbol definitions

src/video/SDL_vulkan_utils.c

@@ -25,21 +25,6 @@
 
 #if SDL_VIDEO_VULKAN
 
-/* Based on the headers found in
- * https://github.com/KhronosGroup/Vulkan-LoaderAndValidationLayers
- */
-#if VK_HEADER_VERSION < 22
-enum
-{
-    VK_ERROR_FRAGMENTED_POOL = -12,
-};
-#endif
-#if VK_HEADER_VERSION < 38
-enum {
-    VK_ERROR_OUT_OF_POOL_MEMORY_KHR = -1000069000
-};
-#endif
-
 const char *SDL_Vulkan_GetResultString(VkResult result)
 {
     switch((int)result)