anv: Don't reject Android image format if external props not supplied

anv: Don't reject Android image format if external props not supplied

anv_GetPhysicalDeviceImageFormatProperties2 returns 'not supported' if an
Android hardware buffer external memory handle type is specified, but no
external image format properties output struct is supplied. This struct is
optional, so we should populate it if present, but return successfully
either way.

This fixes an error when using ANV with hwui, which otherwise prevents the
system from booting.[1]

[1] https://cs.android.com/android/platform/superproject/main/+/main:frameworks/base/libs/hwui/renderthread/VulkanSurface.cpp;l=271;drc=ad3fb95aa2fe0be59d3e991ddc883592ab5542bc

Signed-off-by: Chris Spencer <spencercw@gmail.com>
Reviewed-by: Tapani Pälli <tapani.palli@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24844>