Expose VK_EXT_headless_surface

I implemented this extension as part of swiftshader-cl/51589 but had not
exposed it as a supported extension. This worked fine when loading
SwiftShader directly, but I need to now load it via the loader.

Bug: b/176981107
Change-Id: I494be7154b04186e51ee380e16b60b88ff9c9d30
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/52751
Tested-by: Antonio Maiorano <amaiorano@google.com>
Kokoro-Result: Antonio Maiorano <amaiorano@google.com>
Kokoro-Result: kokoro <noreply+kokoro@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>
diff --git a/src/Vulkan/libVulkan.cpp b/src/Vulkan/libVulkan.cpp
index 39c82f0..9af7ef4 100644
--- a/src/Vulkan/libVulkan.cpp
+++ b/src/Vulkan/libVulkan.cpp
@@ -310,6 +310,7 @@
 	{ VK_KHR_EXTERNAL_SEMAPHORE_CAPABILITIES_EXTENSION_NAME, VK_KHR_EXTERNAL_SEMAPHORE_CAPABILITIES_SPEC_VERSION },
 	{ VK_KHR_GET_PHYSICAL_DEVICE_PROPERTIES_2_EXTENSION_NAME, VK_KHR_GET_PHYSICAL_DEVICE_PROPERTIES_2_SPEC_VERSION },
 	{ VK_EXT_DEBUG_UTILS_EXTENSION_NAME, VK_EXT_DEBUG_UTILS_SPEC_VERSION },
+	{ VK_EXT_HEADLESS_SURFACE_EXTENSION_NAME, VK_EXT_HEADLESS_SURFACE_SPEC_VERSION },
 #ifndef __ANDROID__
 	{ VK_KHR_SURFACE_EXTENSION_NAME, VK_KHR_SURFACE_SPEC_VERSION },
 #endif