libvulkan: update code gen templates

Update code-generator.tmpl to match the result from doing `$ apic
template ../api/vulkan.api code-generator.tmpl`.
Update null_driver.tmpl to match the result from doing `$ apic template
../api/vulkan.api null_driver.tmpl`.

Test: build
Change-Id: Idcf6c148fd0d49bb1b6a31e657e82970f52923c0
diff --git a/vulkan/libvulkan/driver_gen.h b/vulkan/libvulkan/driver_gen.h
index 14c3aba..37b2c6e 100644
--- a/vulkan/libvulkan/driver_gen.h
+++ b/vulkan/libvulkan/driver_gen.h
@@ -21,6 +21,7 @@
 
 #include <vulkan/vk_android_native_buffer.h>
 #include <vulkan/vulkan.h>
+
 #include <bitset>
 
 namespace vulkan {