This reverts commit a7bb6a9b.

Reason for revert: Failing on Ozone builder, see bug.

Bug: angleproject:5289

Original change's description:
> Add support for Linux vulkan backend with VK_KHR_display
>
> Implement Linux simple display mode with vulkan backend
> through VK_KHR_display.
>
> Added value 'EGL_PLATFORM_VULKAN_DISPLAY_MODE_SIMPLE_ANGLE' for
> attribute EGL_PLATFORM_ANGLE_NATIVE_PLATFORM_TYPE_ANGLE to identify
> the new simple display mode. Also reserved
> EGL_PLATFORM_VULKAN_DISPLAY_MODE_HEADLESS_ANGLE for headless mode.
>
> How to enable:
> Add
>
> ```
> use_x11=false
> angle_vulkan_display_mode="simple" # default value
> ```
>
> into args.gn, then compile with linux vulkan args.
>
> Bug: angleproject:5214
> Change-Id: I1247585b9de8b55df106aba99322281f1c183203
> Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2494320
> Commit-Queue: Jamie Madill <jmadill@chromium.org>
> Reviewed-by: Jamie Madill <jmadill@chromium.org>
> Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>

TBR=syoussefi@chromium.org,sunny.sun@arm.com,jmadill@chromium.org,xiaoxuan.liu@arm.com

Change-Id: I3e2a2a044c220ed8d25be0d82184e5fba7b9c06a
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: angleproject:5214
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2514637Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>