anv: fix corner case of mutable descriptor pool creation
What does this MR do and why?
anv: fix corner case of mutable descriptor pool creation
Signed-off-by: Lionel Landwerlin lionel.g.landwerlin@intel.com Fixes: 63e91148 ("anv: Enable VK_VALVE_mutable_descriptor_type") Closes: #10065 (closed)