turnip: Add driver skeleton (v2)

meson files have been updated, autotools and android still need
updating.

Only build tested.

v2 (chadv):
  - Rebase onto master.
  - Fix build breakage in Python scripts.
  - Drop the WSI code. The internal WSI apis have changed recently, and
    will likely change again before the driver goes upstream. To avoid
    unnecessary rebase work, let's drop the WSI code and re-add it when
    we're ready to really use WSI.

(olv, after rebase) do not enable freedreno by default on ARM
diff --git a/meson.build b/meson.build
index 2ccf5f2..8ec0a56 100644
--- a/meson.build
+++ b/meson.build
@@ -203,6 +203,7 @@
 
 with_intel_vk = _vulkan_drivers.contains('intel')
 with_amd_vk = _vulkan_drivers.contains('amd')
+with_freedreno_vk = _vulkan_drivers.contains('freedreno')
 with_any_vk = _vulkan_drivers.length() != 0 and _vulkan_drivers != ['']
 
 if with_dri_swrast and (with_gallium_softpipe or with_gallium_swr)