anv: correctly use vulkan 1.0 by default

Per chapter 3.2 "Instances":
> Providing a NULL VkInstanceCreateInfo::pApplicationInfo or providing
> an apiVersion of 0 is equivalent to providing an apiVersion of
> VK_MAKE_VERSION(1,0,0).

Reported-by: Niklas Haas <git@haasn.xyz>
Fixes: 8c048af5890d43578ca4 "anv: Copy the appliation info into the instance"
Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>