anv: Install as Vulkan HAL module in Android.mk build

anv: Install as Vulkan HAL module in Android.mk build

Now that anvil fully implements the Vulkan HAL interface, we can install
it as the vendor HAL module at /vendor/lib/hw/vulkan.${board}.so. To do
so:

  - Rename LOCAL_MODULE to vulkan.$(TARGET_BOARD_PLATFORM).
  - Use LOCAL_PROPRIETARY_MODULE to install under vendor path.

Tested by running different Sascha Williams demos on Android-IA.

Signed-off-by: Tapani Pälli <tapani.palli@intel.com>
[chadv: Extract this hunk from Tapani's patch, and embed it as
 stand-alone patch in my arc-vulkan series].
Signed-off-by: Chad Versace <chadversary@chromium.org>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>