Vulkan headers: restore vulkan_fuchsia_extras.h include.

A previous CL updated the Vulkan headers, and removed our
include for vulkan_fuchsia_extras.h, which contains
Fuchsia-specific declarations that are used by the platform
but not upstreamed yet to Khronos.

This CL simply restores the include.

Bug: 143197472
Change-Id: I934f185c76f54e08ff52a202198cb951ad4b6644
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/37450
Tested-by: David Turner <digit@google.com>
Presubmit-Ready: David Turner <digit@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Kokoro-Presubmit: David Turner <digit@google.com>
diff --git a/include/vulkan/vulkan.h b/include/vulkan/vulkan.h
index 375964b..a468393 100644
--- a/include/vulkan/vulkan.h
+++ b/include/vulkan/vulkan.h
@@ -27,6 +27,7 @@
 #ifdef VK_USE_PLATFORM_FUCHSIA

 #include <zircon/types.h>

 #include "vulkan_fuchsia.h"

+#include "vulkan_fuchsia_extras.h"

 #endif

 

 #ifdef VK_USE_PLATFORM_IOS_MVK