VK_KHR_shader_float16_int8, don't skip unknown ext. structs

Bug: 160277060

Change-Id: I07a9ccdfa10f79308c88db36fdc70912c2585c7a
diff --git a/system/vulkan/func_table.cpp b/system/vulkan/func_table.cpp
index 721e7c5..50e8a62 100644
--- a/system/vulkan/func_table.cpp
+++ b/system/vulkan/func_table.cpp
@@ -3679,6 +3679,8 @@
 #endif
 #ifdef VK_KHR_8bit_storage
 #endif
+#ifdef VK_KHR_shader_float16_int8
+#endif
 #ifdef VK_ANDROID_native_buffer
 static VkResult entry_vkGetSwapchainGrallocUsageANDROID(
     VkDevice device,