libvulkan: Only load driver functions for enabled extensions

Change-Id: I4105291bd42583a10420681b729f03ecd7a91724
(cherry picked from commit 1c77ae2acda376b791932beffcb931c378e8ee36)
diff --git a/vulkan/libvulkan/dispatch_gen.cpp b/vulkan/libvulkan/dispatch_gen.cpp
index bf9b38f..ebdf0da 100644
--- a/vulkan/libvulkan/dispatch_gen.cpp
+++ b/vulkan/libvulkan/dispatch_gen.cpp
@@ -1198,6 +1198,7 @@
 
 bool LoadDriverDispatchTable(VkInstance instance,
                              PFN_vkGetInstanceProcAddr get_proc_addr,
+                             const InstanceExtensionSet& extensions,
                              DriverDispatchTable& dispatch) {
     bool success = true;
     // clang-format off