Fix presentAt device features to be optional in the xml

Author: nvlduc

xml/vk.xml

@@ -22966,8 +22966,6 @@ typedef void* <name>MTLSharedEvent_id</name>;
                 <command name="vkGetSwapchainTimeDomainPropertiesEXT"/>
                 <command name="vkGetPastPresentationTimingEXT"/>
                 <feature name="presentTiming" struct="VkPhysicalDevicePresentTimingFeaturesEXT"/>
-                <feature name="presentAtAbsoluteTime" struct="VkPhysicalDevicePresentTimingFeaturesEXT"/>
-                <feature name="presentAtRelativeTime" struct="VkPhysicalDevicePresentTimingFeaturesEXT"/>
             </require>
         </extension>
         <extension name="VK_INTEL_shader_integer_functions2" number="210" type="device" depends="VK_KHR_get_physical_device_properties2,VK_VERSION_1_1" author="INTEL" contact="Ian Romanick @ianromanick" supported="vulkan">