loader: bug 12992: extension and layer support

Much of layers and loader updated to work with
final extension and layer mechanism.
Not everything is working here.
diff --git a/loader/table_ops.h b/loader/table_ops.h
index d65fd30..430d811 100644
--- a/loader/table_ops.h
+++ b/loader/table_ops.h
@@ -370,7 +370,7 @@
     table->GetPhysicalDeviceQueueProperties = (PFN_vkGetPhysicalDeviceQueueProperties) gpa(inst, "vkGetPhysicalDeviceQueueProperties");
     table->GetPhysicalDeviceMemoryProperties = (PFN_vkGetPhysicalDeviceMemoryProperties) gpa(inst, "vkGetPhysicalDeviceMemoryProperties");
     table->GetPhysicalDeviceExtensionProperties = (PFN_vkGetPhysicalDeviceExtensionProperties) gpa(inst, "vkGetPhysicalDeviceExtensionProperties");
-    table->GetPhysicalDeviceExtensionCount = (PFN_vkGetPhysicalDeviceExtensionCount) gpa(inst, "vkGetPhysicalDeviceExtensionCount");
+    table->GetPhysicalDeviceLayerProperties = (PFN_vkGetPhysicalDeviceLayerProperties) gpa(inst, "vkGetPhysicalDeviceLayerProperties");
 }
 
 static inline void loader_init_instance_extension_dispatch_table(
@@ -414,10 +414,10 @@
         return (void *) table->GetPhysicalDeviceMemoryProperties;
     if (!strcmp(name, "GetInstanceProcAddr"))
         return (void *) table->GetInstanceProcAddr;
-    if (!strcmp(name, "GetPhysicalDeviceExtensionCount"))
-        return (void *) table->GetPhysicalDeviceExtensionCount;
     if (!strcmp(name, "GetPhysicalDeviceExtensionProperties"))
         return (void *) table->GetPhysicalDeviceExtensionProperties;
+    if (!strcmp(name, "GetPhysicalDeviceLayerProperties"))
+        return (void *) table->GetPhysicalDeviceLayerProperties;
     if (!strcmp(name, "DbgCreateMsgCallback"))
         return (void *) table->DbgCreateMsgCallback;
     if (!strcmp(name, "DbgDestroyMsgCallback"))