Temporarily disable enumeration of VK_KHR_incremental_present

Test: Ran the instrumented cube demo, which showed the extension not
enumerated.

Since the extension is not yet ratified, we can't enable it in the
upcoming DP1 release.

Change-Id: I8234c2d9510a0d31c309fb2c25fe6126fb021a59
diff --git a/vulkan/libvulkan/driver.cpp b/vulkan/libvulkan/driver.cpp
index 32f777d..a23056c 100644
--- a/vulkan/libvulkan/driver.cpp
+++ b/vulkan/libvulkan/driver.cpp
@@ -739,8 +739,10 @@
     const InstanceData& data = GetData(physicalDevice);
     static const std::array<VkExtensionProperties, 2> loader_extensions = {{
         // WSI extensions
+#if 0 // Remove this "#if 0" once the VK_KHR_incremental_present extension is ratified
         {VK_KHR_INCREMENTAL_PRESENT_EXTENSION_NAME,
          VK_KHR_INCREMENTAL_PRESENT_SPEC_VERSION},
+#endif
         {VK_GOOGLE_DISPLAY_TIMING_EXTENSION_NAME,
          VK_GOOGLE_DISPLAY_TIMING_SPEC_VERSION},
     }};